@import url("https://fonts.googleapis.com/css2?family=Newsreader:ital,opsz,wght@0,6..72,300;0,6..72,400;0,6..72,500;1,6..72,300;1,6..72,400&family=Inter:wght@300;400;500;600&family=IBM+Plex+Mono:wght@300;400;500&display=swap");

:root {
  --bg: #070b16;
  --bg-deep: #02030a;
  --surface: rgba(13, 20, 38, 0.78);
  --surface-strong: rgba(13, 20, 38, 0.94);
  --surface-soft: rgba(255, 255, 255, 0.06);
  --line: rgba(187, 222, 255, 0.16);
  --line-strong: rgba(118, 232, 255, 0.34);
  --text: #eef2fb;
  --muted: #9aa6c6;
  --muted-strong: #c8d2eb;
  --cyan: #52d6e6;
  --violet: #9488f7;
  --mint: #9fffd2;
  --gold: #edb24e;
  --rose: #ff7ea8;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.42);
  --radius: 8px;
  --header-height: 76px;
  --motion-ease: cubic-bezier(0.22, 1, 0.36, 1);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 18px);
}

body {
  margin: 0;
  min-width: 320px;
  color: var(--text);
  background:
    radial-gradient(circle at 18% 12%, rgba(95, 231, 255, 0.14), transparent 28rem),
    radial-gradient(circle at 80% 14%, rgba(169, 140, 255, 0.13), transparent 32rem),
    radial-gradient(circle at 42% 88%, rgba(244, 201, 107, 0.08), transparent 26rem),
    var(--bg);
  line-height: 1.6;
}

body.is-ready main {
  animation: pageFadeUp 780ms var(--motion-ease) both;
}

body.page-leaving main {
  opacity: 0;
  transform: translateY(8px);
  transition:
    opacity 180ms ease,
    transform 180ms var(--motion-ease);
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -2;
  content: "";
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: linear-gradient(to bottom, black, transparent 82%);
  animation: fieldDrift 24s linear infinite;
}

body::after {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  background:
    linear-gradient(180deg, rgba(2, 3, 10, 0.34), rgba(2, 3, 10, 0.78)),
    url("assets/quantum-field.png") center top / cover no-repeat;
  opacity: 0.42;
  animation: ambientField 18s var(--motion-ease) infinite alternate;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity 720ms var(--motion-ease),
    transform 720ms var(--motion-ease),
    border-color 360ms ease,
    background 360ms ease,
    box-shadow 360ms ease;
  transition-delay: var(--reveal-delay, 0ms);
  will-change: opacity, transform;
}

.reveal.in-view {
  opacity: 1;
  transform: translateY(0);
}

body.simulator-page.is-ready main {
  animation: none !important;
}

body.simulator-page main,
body.simulator-page .reveal,
body.simulator-page .reveal-on-scroll,
body.simulator-page .scroll-reveal,
body.simulator-page .fade-up,
body.simulator-page [data-reveal],
body.simulator-page [data-scroll-reveal] {
  opacity: 1 !important;
  transform: none !important;
  visibility: visible !important;
  animation: none !important;
  transition-delay: 0ms !important;
}

body.simulator-page .reveal.in-view,
body.simulator-page .reveal-on-scroll.is-visible,
body.simulator-page .scroll-reveal.is-visible,
body.simulator-page .fade-up.is-visible {
  opacity: 1 !important;
  transform: none !important;
  visibility: visible !important;
}

@keyframes pageFadeUp {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fieldDrift {
  from {
    background-position: 0 0, 0 0;
  }
  to {
    background-position: 64px 64px, 64px 64px;
  }
}

@keyframes ambientField {
  from {
    opacity: 0.34;
    transform: scale(1);
  }
  to {
    opacity: 0.48;
    transform: scale(1.025);
  }
}

a {
  color: inherit;
  text-decoration: none;
}

p {
  margin: 0;
  color: var(--muted);
}

h1,
h2,
h3 {
  font-family: Newsreader, Georgia, "Times New Roman", serif;
  margin: 0;
  color: var(--text);
  line-height: 1.08;
  letter-spacing: 0;
}

h1 {
  max-width: 990px;
  font-size: clamp(2.9rem, 6vw, 5.55rem);
}

h2 {
  font-size: clamp(2rem, 4vw, 4.1rem);
}

h3 {
  font-size: 1.08rem;
}

button,
input,
select {
  font: inherit;
}

.page-shell {
  width: min(1160px, calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  height: var(--header-height);
  padding: 0 max(20px, calc((100vw - 1160px) / 2));
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(3, 5, 14, 0.62);
  backdrop-filter: blur(22px);
  transition: background 220ms ease, border-color 220ms ease;
}

.site-header.is-scrolled {
  border-color: rgba(95, 231, 255, 0.22);
  background: rgba(3, 5, 14, 0.86);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.72rem;
  min-width: 0;
  font-weight: 720;
  letter-spacing: 0;
}

.brand-mark {
  position: relative;
  flex: 0 0 auto;
  width: 28px;
  height: 28px;
  border: 1px solid rgba(95, 231, 255, 0.72);
  border-radius: 50%;
  box-shadow: 0 0 24px rgba(95, 231, 255, 0.34), inset 0 0 18px rgba(169, 140, 255, 0.2);
}

.brand-mark::before,
.brand-mark::after {
  position: absolute;
  inset: 5px;
  content: "";
  border: 1px solid rgba(244, 201, 107, 0.58);
  border-radius: 50%;
  transform: rotate(58deg) scaleX(1.85);
}

.brand-mark::after {
  border-color: rgba(159, 255, 210, 0.48);
  transform: rotate(-34deg) scaleX(1.65);
}

.main-nav {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.main-nav a {
  position: relative;
  z-index: 1;
  display: inline-flex;
  align-items: center;
  min-height: 38px;
  padding: 0 0.78rem;
  border: 1px solid transparent;
  border-radius: 999px;
  color: var(--muted-strong);
  font-size: 0.92rem;
  transition: color 180ms ease, border-color 180ms ease, background 180ms ease;
}

.main-nav a:hover {
  border-color: rgba(95, 231, 255, 0.22);
  color: var(--text);
  background: rgba(255, 255, 255, 0.07);
}

.main-nav a.is-active,
.main-nav a[aria-current="page"] {
  border-color: transparent;
  color: var(--text);
  background: transparent;
}

.nav-active-pill {
  position: absolute;
  z-index: 0;
  left: 0;
  top: 0;
  width: 0;
  height: 38px;
  border: 1px solid rgba(82, 214, 230, 0.22);
  border-radius: 999px;
  background:
    linear-gradient(135deg, rgba(82, 214, 230, 0.14), rgba(148, 136, 247, 0.1)),
    rgba(255, 255, 255, 0.055);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.08),
    0 12px 30px rgba(82, 214, 230, 0.1);
  opacity: 0;
  pointer-events: none;
  transition:
    transform 520ms var(--motion-ease),
    width 520ms var(--motion-ease),
    height 520ms var(--motion-ease),
    opacity 300ms ease;
}

.main-nav.has-active-pill .nav-active-pill {
  opacity: 1;
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  border-radius: 999px;
  background: currentColor;
  transition: transform 180ms ease;
}

.menu-toggle[aria-expanded="true"] span:first-child {
  transform: translateY(3.5px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] span:last-child {
  transform: translateY(-3.5px) rotate(-45deg);
}

.hero {
  position: relative;
  display: grid;
  min-height: min(700px, 78svh);
  padding: 124px 0 58px;
  overflow: hidden;
  isolation: isolate;
  background:
    linear-gradient(90deg, rgba(2, 3, 10, 0.92), rgba(2, 3, 10, 0.48) 58%, rgba(2, 3, 10, 0.82)),
    url("assets/quantum-field.png") center / cover no-repeat;
}

.hero::after,
.simulator-hero::after {
  position: absolute;
  inset: auto 0 0;
  height: 28%;
  content: "";
  background: linear-gradient(to bottom, transparent, var(--bg));
  pointer-events: none;
  z-index: -1;
}

.particle-canvas {
  position: absolute;
  inset: 0;
  z-index: -1;
  width: 100%;
  height: 100%;
  opacity: 0.72;
}

.hero-inner {
  align-self: center;
}

.eyebrow,
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  margin-bottom: 1rem;
  color: var(--cyan);
  font-size: 0.78rem;
  font-weight: 760;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.eyebrow::before,
.section-kicker::before {
  width: 30px;
  height: 1px;
  content: "";
  background: linear-gradient(90deg, var(--cyan), var(--gold));
}

.hero-copy {
  max-width: 710px;
  margin-top: 1.4rem;
  color: #d8e4f2;
  font-size: clamp(1.08rem, 2vw, 1.34rem);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 2rem;
}

.button {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.78rem 1.1rem;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: var(--radius);
  font-weight: 760;
  overflow: hidden;
  transition:
    transform 260ms var(--motion-ease),
    border-color 260ms ease,
    background 260ms ease,
    box-shadow 260ms ease,
    color 260ms ease;
}

.button::after,
.mini-button::after,
.quantum-button::after,
.inline-link::after {
  position: absolute;
  inset: 0;
  content: "";
  pointer-events: none;
  background: linear-gradient(110deg, transparent 0 35%, rgba(255, 255, 255, 0.18) 48%, transparent 62% 100%);
  opacity: 0;
  transform: translateX(-72%);
  transition:
    opacity 260ms ease,
    transform 680ms var(--motion-ease);
}

.button:hover {
  transform: translateY(-2px);
  border-color: rgba(82, 214, 230, 0.55);
  box-shadow: 0 20px 48px rgba(82, 214, 230, 0.16);
}

.button:hover::after,
.mini-button:hover::after,
.quantum-button:hover::after,
.inline-link:hover::after {
  opacity: 1;
  transform: translateX(72%);
}

.button:active,
.mini-button:active,
.quantum-button:active,
.segmented-control button:active,
.answer-grid button:active,
.theory-tabs button:active {
  transform: translateY(0) scale(0.985);
}

.button.primary {
  border-color: rgba(95, 231, 255, 0.52);
  color: #031018;
  background: linear-gradient(135deg, var(--cyan), var(--mint));
  box-shadow: 0 18px 42px rgba(95, 231, 255, 0.22);
}

.button.secondary {
  color: var(--text);
  background: rgba(255, 255, 255, 0.08);
}

.button.secondary:hover {
  border-color: rgba(244, 201, 107, 0.42);
  background: rgba(255, 255, 255, 0.12);
}

.content-band,
.quote-section,
.simulator-lab {
  position: relative;
  padding: 112px 0;
}

.content-band.darker,
.simulator-lab {
  background:
    radial-gradient(circle at 18% 0%, rgba(95, 231, 255, 0.08), transparent 34rem),
    linear-gradient(180deg, rgba(255, 255, 255, 0.035), rgba(255, 255, 255, 0));
}

.split-layout,
.objective-layout,
.future-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  gap: clamp(2rem, 5vw, 5rem);
  align-items: start;
}

.text-column {
  display: grid;
  gap: 1.1rem;
  font-size: 1.04rem;
}

.section-heading {
  max-width: 840px;
  margin-bottom: 2.2rem;
}

.section-heading p:last-child {
  margin-top: 1rem;
  font-size: 1.04rem;
}

.section-heading.compact {
  margin-bottom: 1.6rem;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.topic-card,
.formula-panel,
.quote-block,
.lab-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.085), rgba(255, 255, 255, 0.035));
  box-shadow: var(--shadow);
  backdrop-filter: blur(22px);
  transition:
    transform 420ms var(--motion-ease),
    border-color 420ms ease,
    background 420ms ease,
    box-shadow 420ms ease;
}

.topic-card {
  min-height: 194px;
  padding: 1.1rem;
  transition: transform 190ms ease, border-color 190ms ease, background 190ms ease;
}

.topic-card:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
  background: linear-gradient(180deg, rgba(95, 231, 255, 0.11), rgba(255, 255, 255, 0.04));
}

.topic-card span,
.timeline span {
  color: var(--gold);
  font-size: 0.78rem;
  font-weight: 780;
}

.topic-card h3 {
  margin-top: 1.1rem;
}

.topic-card p {
  margin-top: 0.7rem;
  font-size: 0.95rem;
}

.formula-panel {
  padding: 1.35rem;
}

.formula-label {
  margin-bottom: 0.75rem;
  color: var(--mint);
  font-size: 0.82rem;
  font-weight: 760;
  text-transform: uppercase;
}

.formula {
  padding: 1.2rem;
  border: 1px solid rgba(95, 231, 255, 0.22);
  border-radius: var(--radius);
  color: #f7fbff;
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.12), rgba(169, 140, 255, 0.1)),
    rgba(0, 0, 0, 0.24);
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: clamp(1.35rem, 3vw, 2.3rem);
  text-align: center;
  white-space: nowrap;
  overflow-x: auto;
}

.formula-panel p:last-child {
  margin-top: 1rem;
}

.timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  padding: 0;
  margin: 0;
  list-style: none;
  counter-reset: item;
}

.timeline li {
  position: relative;
  min-height: 142px;
  padding: 1.05rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(7, 11, 23, 0.74);
}

.timeline li::after {
  position: absolute;
  right: -0.72rem;
  top: 50%;
  width: 0.72rem;
  height: 1px;
  content: "";
  background: linear-gradient(90deg, var(--cyan), transparent);
}

.timeline li:nth-child(4n)::after,
.timeline li:last-child::after {
  content: none;
}

.timeline strong {
  display: block;
  margin-top: 0.9rem;
  color: var(--text);
  font-size: 1rem;
  line-height: 1.35;
}

.quote-section {
  background:
    linear-gradient(rgba(2, 3, 10, 0.72), rgba(2, 3, 10, 0.9)),
    url("assets/quantum-field.png") center 42% / cover no-repeat;
}

.quote-block {
  max-width: 820px;
  margin: 0 auto;
  padding: clamp(1.5rem, 5vw, 3.5rem);
  text-align: center;
}

.quote-block p {
  color: var(--text);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.35rem, 3.2vw, 2.65rem);
  line-height: 1.35;
}

.quote-block figcaption {
  margin-top: 1.6rem;
  color: var(--gold);
  font-weight: 760;
}

.quote-block figcaption span {
  display: block;
  margin-top: 0.24rem;
  color: var(--muted);
  font-weight: 500;
}

.future-band {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.future-layout {
  align-items: center;
}

.future-layout .button {
  justify-self: end;
}

.site-footer {
  padding: 30px 0;
  background: rgba(2, 3, 10, 0.86);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.5rem;
  justify-content: space-between;
  font-size: 0.92rem;
}

.simulator-hero {
  position: relative;
  min-height: min(560px, 68svh);
  padding: 124px 0 58px;
  overflow: hidden;
  isolation: isolate;
  background:
    linear-gradient(90deg, rgba(2, 3, 10, 0.94), rgba(2, 3, 10, 0.58) 58%, rgba(2, 3, 10, 0.86)),
    url("assets/quantum-field.png") center / cover no-repeat;
}

.simulator-intro {
  max-width: 980px;
}

.simulator-intro h1 {
  font-size: clamp(2.55rem, 5.2vw, 4.9rem);
}

.simulator-intro > p {
  max-width: 760px;
  margin-top: 1.2rem;
  color: #dbe6f3;
  font-size: clamp(1.05rem, 2vw, 1.24rem);
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
  max-width: 720px;
  margin-top: 2rem;
}

.simulator-guide {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.65rem;
  max-width: 900px;
  margin-top: 1.5rem;
}

.simulator-guide span {
  min-height: 54px;
  padding: 0.78rem 0.82rem;
  border: 1px solid rgba(95, 231, 255, 0.18);
  border-radius: var(--radius);
  color: var(--muted-strong);
  background: rgba(3, 7, 18, 0.48);
  backdrop-filter: blur(14px);
  font-size: 0.9rem;
  font-weight: 760;
}

.mode-switch {
  display: inline-grid;
  grid-auto-flow: column;
  gap: 0.36rem;
  align-items: center;
  margin-top: 1rem;
  padding: 0.35rem;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius);
  background: rgba(3, 7, 18, 0.46);
  backdrop-filter: blur(12px);
}

.mode-switch span {
  padding: 0 0.44rem;
  color: var(--muted-strong);
  font-size: 0.82rem;
  font-weight: 760;
}

.mode-switch button {
  min-height: 34px;
  padding: 0.4rem 0.7rem;
  border: 1px solid transparent;
  border-radius: calc(var(--radius) - 4px);
  color: var(--muted-strong);
  background: transparent;
  cursor: pointer;
  font-weight: 760;
}

.mode-switch button.is-active {
  border-color: rgba(95, 231, 255, 0.36);
  color: var(--text);
  background: rgba(95, 231, 255, 0.13);
}

.hero-metrics div,
.amplitude-grid div,
.readout-row div,
.purity-readout,
.state-type {
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.055);
}

.hero-metrics div {
  padding: 0.88rem;
  backdrop-filter: blur(18px);
}

.hero-metrics span,
.amplitude-grid span,
.readout-row span,
.purity-readout span,
.state-type span {
  display: block;
  color: var(--muted);
  font-size: 0.8rem;
}

.hero-metrics strong,
.amplitude-grid strong,
.readout-row strong,
.purity-readout strong,
.state-type strong {
  display: block;
  margin-top: 0.24rem;
  color: var(--text);
  font-size: 1.12rem;
}

.lab-grid,
.simulator-flow {
  display: flex;
  flex-direction: column;
  gap: clamp(2.6rem, 5vw, 4.2rem);
}

.simulator-section {
  display: grid;
  gap: 1.35rem;
}

.simulator-section-header {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 1rem;
  align-items: start;
  max-width: 980px;
}

.simulator-section-header h2 {
  font-size: clamp(1.65rem, 3.2vw, 3rem);
}

.simulator-section-header p:last-child {
  max-width: 760px;
  margin-top: 0.55rem;
  color: var(--muted-strong);
  font-size: 1rem;
}

.simulator-section-index {
  display: grid;
  width: 44px;
  aspect-ratio: 1;
  place-items: center;
  border: 1px solid rgba(95, 231, 255, 0.32);
  border-radius: var(--radius);
  color: var(--cyan);
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.16), rgba(169, 140, 255, 0.08)),
    rgba(4, 8, 20, 0.74);
  box-shadow: 0 16px 34px rgba(95, 231, 255, 0.12);
  font-weight: 860;
}

.simulator-main-grid {
  display: grid;
  grid-template-columns: minmax(320px, 0.92fr) minmax(420px, 1.08fr);
  gap: 1.3rem;
  align-items: start;
}

.state-definition-grid,
.simulator-visual-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.3rem;
  align-items: start;
  max-width: 980px;
}

.simulator-state-stack,
.simulator-support-grid,
.simulator-learning-grid,
.simulator-export-grid {
  display: grid;
  gap: 1rem;
}

.simulator-results-grid,
.simulator-decoherence-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  align-items: stretch;
}

.simulator-support-grid {
  grid-template-columns: minmax(0, 1.1fr) minmax(320px, 0.9fr);
  margin-top: 1rem;
}

.simulator-learning-grid {
  grid-template-columns: minmax(0, 1.08fr) minmax(300px, 0.92fr);
}

.simulator-learning-grid .challenges-panel {
  grid-column: 1 / -1;
}

.simulator-export-grid {
  grid-template-columns: minmax(0, 1.04fr) minmax(320px, 0.96fr);
}

.lab-panel {
  position: relative;
  min-width: 0;
  padding: 1.18rem;
  overflow: hidden;
}

.lab-panel::before {
  position: absolute;
  inset: 0;
  content: "";
  pointer-events: none;
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.1), transparent 38%),
    radial-gradient(circle at 90% 0%, rgba(169, 140, 255, 0.12), transparent 16rem);
  opacity: 0.78;
}

.lab-panel > * {
  position: relative;
}

.controls-panel {
  grid-area: controls;
}

.ket-panel {
  grid-area: ket;
}

.probability-panel {
  grid-area: probabilities;
}

.matrix-panel {
  grid-area: matrix;
}

.coherence-panel {
  grid-area: coherence;
}

.purity-panel {
  grid-area: purity;
}

.bloch-panel {
  grid-area: bloch;
}

.chart-panel {
  grid-area: chart;
}

.explanation-panel {
  grid-area: explain;
}

.compare-panel {
  grid-area: compare;
}

.environment-panel {
  grid-area: environment;
}

.measurement-panel {
  grid-area: measure;
}

.steps-panel {
  grid-area: steps;
}

.challenges-panel {
  grid-area: challenges;
}

.report-panel {
  grid-area: report;
}

.glossary-panel {
  grid-area: glossary;
}

.simulator-flow .controls-panel,
.simulator-flow .ket-panel,
.simulator-flow .probability-panel,
.simulator-flow .matrix-panel,
.simulator-flow .coherence-panel,
.simulator-flow .purity-panel,
.simulator-flow .bloch-panel,
.simulator-flow .chart-panel,
.simulator-flow .explanation-panel,
.simulator-flow .compare-panel,
.simulator-flow .environment-panel,
.simulator-flow .measurement-panel,
.simulator-flow .steps-panel,
.simulator-flow .challenges-panel,
.simulator-flow .report-panel,
.simulator-flow .glossary-panel {
  grid-area: auto;
}

.panel-heading {
  margin-bottom: 1.15rem;
}

.panel-heading h2 {
  font-size: clamp(1.25rem, 2vw, 1.68rem);
}

.panel-heading p:not(.section-kicker) {
  margin-top: 0.38rem;
  color: var(--muted-strong);
  font-size: 0.95rem;
}

.control-cluster {
  display: grid;
  gap: 0.62rem;
  padding: 0.86rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.035);
}

.control-cluster + .control-cluster {
  margin-top: 0.85rem;
}

.control-cluster h3 {
  color: var(--cyan);
  font-size: 0.8rem;
  font-weight: 840;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.control-group {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.6rem 1rem;
  align-items: center;
  max-width: 100%;
  padding: 1rem 0;
  overflow: hidden;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  color: var(--muted-strong);
}

.control-group > * {
  min-width: 0;
}

.control-cluster .control-group:first-of-type {
  padding-top: 0;
  border-top: 0;
}

.custom-controls[hidden] {
  display: none;
}

.custom-controls {
  display: grid;
  gap: 0.85rem;
  margin-top: 0.9rem;
}

.coefficient-field {
  margin-inline: -0.18rem;
  padding-inline: 0.18rem;
  border-radius: var(--radius);
  transition: background 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.coefficient-field.is-active {
  background: rgba(95, 231, 255, 0.055);
  box-shadow: inset 3px 0 0 rgba(95, 231, 255, 0.72);
}

.norm-status {
  margin: 0.72rem 0 0.25rem;
  padding: 0.64rem 0.72rem;
  border: 1px solid rgba(95, 231, 255, 0.24);
  border-radius: var(--radius);
  color: rgba(227, 253, 255, 0.95);
  background: rgba(95, 231, 255, 0.08);
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 0.95rem;
}

.norm-status.is-warning {
  border-color: rgba(244, 201, 107, 0.42);
  color: #ffe6a6;
  background: rgba(244, 201, 107, 0.08);
}

.norm-status.is-error {
  border-color: rgba(255, 126, 168, 0.42);
  color: #ffd1dc;
  background: rgba(255, 126, 168, 0.08);
}

.control-group span {
  min-width: 0;
  font-weight: 680;
}

.control-group input,
.control-group select {
  grid-column: 1 / -1;
  width: 100%;
}

.control-group output {
  color: var(--cyan);
  font-weight: 760;
  white-space: nowrap;
}

input[type="range"] {
  accent-color: var(--cyan);
}

input[type="text"] {
  min-height: 44px;
  padding: 0.62rem 0.75rem;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(3, 7, 18, 0.86);
  outline: none;
  transition: border-color 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

input[type="text"]:focus {
  border-color: rgba(95, 231, 255, 0.56);
  background: rgba(8, 14, 28, 0.94);
  box-shadow: 0 0 0 3px rgba(95, 231, 255, 0.12);
}

select {
  min-height: 44px;
  padding: 0.62rem 0.75rem;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  color: var(--text);
  background: #0b1020;
}

.state-actions,
.preset-buttons {
  display: grid;
  gap: 0.6rem;
}

.state-actions {
  grid-template-columns: 1fr;
  padding: 0.9rem 0 0.4rem;
}

.preset-buttons {
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-bottom: 1rem;
}

.mini-button,
.preset-button {
  position: relative;
  min-height: 42px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.07);
  cursor: pointer;
  transition:
    transform 260ms var(--motion-ease),
    border-color 260ms ease,
    background 260ms ease,
    box-shadow 260ms ease;
}

.mini-button:hover,
.preset-button:hover,
.preset-button.is-active {
  border-color: rgba(95, 231, 255, 0.42);
  background: rgba(95, 231, 255, 0.12);
  box-shadow: 0 12px 26px rgba(95, 231, 255, 0.12);
}

.mini-button:hover,
.preset-button:hover {
  transform: translateY(-1px);
}

.preset-button.is-active {
  animation: selectedControlPulse 520ms var(--motion-ease) both;
}

.mini-button {
  width: 100%;
  min-height: 56px;
  padding: 0.72rem 0.95rem;
  font-weight: 760;
  font-size: clamp(0.9rem, 1.5vw, 1rem);
  line-height: 1.2;
  text-align: center;
  white-space: normal;
  overflow-wrap: break-word;
}

.mini-button.ghost {
  color: var(--muted-strong);
  background: rgba(255, 255, 255, 0.045);
}

.preset-button {
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 1.15rem;
  font-weight: 760;
}

.math-keyboard {
  margin: 0.85rem 0 0.65rem;
  padding: 0.78rem;
  border: 1px solid rgba(95, 231, 255, 0.16);
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 18% 0%, rgba(95, 231, 255, 0.13), transparent 12rem),
    linear-gradient(145deg, rgba(255, 255, 255, 0.07), rgba(255, 255, 255, 0.025));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08), 0 18px 42px rgba(2, 6, 18, 0.22);
}

.math-keyboard-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.7rem;
  margin-bottom: 0.65rem;
}

.math-keyboard-head span {
  color: var(--cyan);
  font-size: 0.72rem;
  font-weight: 860;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.math-keyboard-head strong {
  padding: 0.28rem 0.48rem;
  border: 1px solid rgba(95, 231, 255, 0.22);
  border-radius: calc(var(--radius) - 4px);
  color: var(--text);
  background: rgba(0, 0, 0, 0.2);
  font-size: 0.78rem;
  white-space: nowrap;
}

.symbolic-state {
  margin-bottom: 0.7rem;
  padding: 0.62rem 0.66rem;
  border: 1px solid rgba(169, 140, 255, 0.18);
  border-radius: calc(var(--radius) - 2px);
  color: rgba(244, 248, 255, 0.92);
  background: rgba(2, 5, 16, 0.34);
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 0.95rem;
  line-height: 1.35;
  overflow-wrap: anywhere;
}

.math-key-grid,
.math-state-presets {
  display: grid;
  gap: 0.42rem;
}

.math-key-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.math-state-presets {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-top: 0.62rem;
  padding-top: 0.62rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.math-state-presets > span {
  grid-column: 1 / -1;
  color: var(--cyan);
  font-size: 0.72rem;
  font-weight: 840;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.math-key-grid button,
.math-state-presets button {
  min-width: 0;
  min-height: 38px;
  padding: 0.5rem 0.4rem;
  border: 1px solid rgba(255, 255, 255, 0.13);
  border-radius: calc(var(--radius) - 3px);
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.07);
  cursor: pointer;
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 0.98rem;
  font-weight: 780;
  transition: transform 140ms ease, border-color 140ms ease, background 140ms ease, box-shadow 140ms ease;
}

.math-key-grid button:hover,
.math-state-presets button:hover,
.math-state-presets button.is-active {
  border-color: rgba(95, 231, 255, 0.44);
  background: rgba(95, 231, 255, 0.13);
  box-shadow: 0 10px 22px rgba(95, 231, 255, 0.12);
}

.math-key-grid button:active,
.math-state-presets button:active {
  transform: translateY(1px) scale(0.98);
}

.math-key-grid .math-command {
  color: var(--muted-strong);
  font-family: inherit;
  font-size: 0.78rem;
  text-transform: uppercase;
}

.state-status {
  min-height: 2.7rem;
  padding: 0.72rem;
  border: 1px solid rgba(159, 255, 210, 0.18);
  border-radius: var(--radius);
  color: var(--muted-strong);
  background: rgba(0, 0, 0, 0.18);
  font-size: 0.9rem;
}

.state-status.is-warning {
  border-color: rgba(244, 201, 107, 0.38);
  color: #ffe6a6;
  background: rgba(244, 201, 107, 0.08);
}

.state-status.is-error {
  border-color: rgba(255, 126, 168, 0.42);
  color: #ffd1dc;
  background: rgba(255, 126, 168, 0.08);
}

.ket-display,
.probability-equations,
.matrix {
  font-family: "Cambria Math", Cambria, Georgia, serif;
}

.ket-display {
  padding: clamp(1rem, 3vw, 1.45rem);
  border: 1px solid rgba(95, 231, 255, 0.24);
  border-radius: var(--radius);
  color: #f8fbff;
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.14), rgba(169, 140, 255, 0.08)),
    rgba(0, 0, 0, 0.2);
  font-size: clamp(1.28rem, 3vw, 2.15rem);
  line-height: 1.35;
  transition:
    border-color 360ms ease,
    box-shadow 360ms ease,
    background 360ms ease;
}

.ket-display.value-pulse,
.readout-pulse,
.measurement-result.result-pulse,
.progress-pill.progress-pulse {
  animation: valuePulse 650ms var(--motion-ease) both;
}

.formula-caption {
  margin-top: 0.85rem;
  color: var(--muted-strong);
}

.amplitude-grid,
.readout-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.72rem;
  margin-top: 1rem;
}

.amplitude-grid div,
.readout-row div,
.purity-readout,
.state-type {
  padding: 0.86rem;
}

.coefficient-field:focus-within,
.pdf-mode-field:focus-within,
.control-group:focus-within {
  border-color: rgba(82, 214, 230, 0.38);
  box-shadow: 0 0 0 3px rgba(82, 214, 230, 0.08);
}

.development-panel {
  margin-top: 0;
  padding-top: 1.18rem;
  border-top: 1px solid var(--line);
}

.simulator-accordion {
  position: relative;
}

.simulator-accordion-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  min-height: 72px;
  padding: 0.1rem 0 0.25rem;
  border: 0;
  color: var(--text);
  background: transparent;
  cursor: pointer;
  text-align: left;
}

.simulator-accordion-trigger span {
  display: grid;
  gap: 0.18rem;
  min-width: 0;
}

.simulator-accordion-trigger small {
  color: var(--cyan);
  font-size: 0.72rem;
  font-weight: 840;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.simulator-accordion-trigger strong {
  font-size: clamp(1.12rem, 1.9vw, 1.45rem);
  line-height: 1.15;
}

.simulator-accordion-trigger em {
  flex: 0 0 auto;
  padding: 0.48rem 0.62rem;
  border: 1px solid rgba(95, 231, 255, 0.24);
  border-radius: var(--radius);
  color: var(--muted-strong);
  background: rgba(95, 231, 255, 0.08);
  font-size: 0.82rem;
  font-style: normal;
  font-weight: 780;
}

.simulator-accordion.is-open .simulator-accordion-trigger {
  margin-bottom: 0.95rem;
  padding-bottom: 0.95rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.simulator-accordion.is-open .simulator-accordion-trigger em {
  color: var(--cyan);
}

.simulator-accordion-body {
  display: grid;
  gap: 0.9rem;
  overflow: hidden;
  max-height: var(--accordion-height, none);
  opacity: 1;
  transform: translateY(0);
  transition:
    max-height 460ms var(--motion-ease),
    opacity 280ms ease,
    transform 360ms var(--motion-ease);
}

.simulator-accordion-body.is-collapsed,
.simulator-inline-accordion-body.is-collapsed,
.concept-content.is-collapsed {
  max-height: 0 !important;
  opacity: 0;
  transform: translateY(-6px);
  pointer-events: none;
}

.simulator-inline-accordion {
  border: 1px solid rgba(95, 231, 255, 0.16);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.07), rgba(169, 140, 255, 0.035)),
    rgba(0, 0, 0, 0.14);
  overflow: hidden;
}

.simulator-inline-accordion-trigger {
  position: relative;
  width: 100%;
  min-height: 48px;
  padding: 0.74rem 2.25rem 0.74rem 0.86rem;
  border: 0;
  color: var(--cyan);
  background: transparent;
  cursor: pointer;
  font-weight: 820;
  text-align: left;
}

.simulator-inline-accordion-trigger::after {
  position: absolute;
  top: 50%;
  right: 0.86rem;
  content: "+";
  transform: translateY(-50%);
  color: var(--violet);
  font-size: 1.15rem;
}

.simulator-inline-accordion-body {
  overflow: hidden;
  max-height: var(--accordion-height, none);
  opacity: 1;
  transform: translateY(0);
  transition:
    max-height 460ms var(--motion-ease),
    opacity 280ms ease,
    transform 360ms var(--motion-ease);
}

.simulator-inline-accordion-trigger[aria-expanded="true"]::after {
  content: "−";
}

.simulator-inline-accordion.is-open .simulator-inline-accordion-trigger {
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.development-head {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
  align-items: start;
  margin-bottom: 0.85rem;
}

.development-head h3 {
  font-size: clamp(1.05rem, 1.8vw, 1.34rem);
}

.development-actions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 0.72rem;
  width: 100%;
}

.pdf-mode-field {
  display: grid;
  gap: 0.38rem;
  min-width: 180px;
  width: 100%;
}

.pdf-mode-field span {
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 760;
}

.pdf-mode-field select {
  width: 100%;
  min-height: 56px;
  padding: 0.72rem 0.82rem;
  font-size: clamp(0.9rem, 1.5vw, 1rem);
  line-height: 1.2;
}

.development-steps {
  display: grid;
  gap: 0.68rem;
}

.development-step,
.report-preview-section {
  border: 1px solid rgba(95, 231, 255, 0.16);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.07), rgba(169, 140, 255, 0.04)),
    rgba(0, 0, 0, 0.18);
  overflow: hidden;
}

.development-step summary {
  position: relative;
  padding: 0.78rem 2.2rem 0.78rem 0.86rem;
  color: var(--cyan);
  cursor: pointer;
  font-weight: 820;
  list-style: none;
}

.development-step summary::-webkit-details-marker {
  display: none;
}

.development-step summary::after {
  position: absolute;
  top: 50%;
  right: 0.86rem;
  content: "+";
  color: var(--violet);
  transform: translateY(-50%);
  font-size: 1.15rem;
}

.development-step[open] summary::after {
  content: "−";
}

.development-step p,
.report-preview-section p {
  margin: 0;
  padding: 0 0.86rem 0.78rem;
  color: var(--muted-strong);
  line-height: 1.58;
}

.development-conclusion {
  color: #eafcff !important;
  font-weight: 760;
}

.formula-stack {
  display: grid;
  gap: 0.42rem;
  padding: 0 0.86rem 0.78rem;
}

.formula-stack code {
  display: block;
  max-width: 100%;
  padding: 0.58rem 0.65rem;
  overflow-x: auto;
  border: 1px solid rgba(95, 231, 255, 0.14);
  border-radius: calc(var(--radius) - 2px);
  color: #f8fbff;
  background: rgba(3, 7, 18, 0.72);
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 0.98rem;
  line-height: 1.45;
  white-space: nowrap;
}

.probability-equations {
  display: flex;
  flex-wrap: wrap;
  gap: 0.62rem;
  margin-bottom: 1rem;
}

.probability-equations span {
  padding: 0.44rem 0.62rem;
  border: 1px solid rgba(95, 231, 255, 0.18);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(0, 0, 0, 0.18);
}

.probability-row + .probability-row {
  margin-top: 1rem;
}

.probability-label {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.8rem;
  margin-bottom: 0.45rem;
}

.probability-label span {
  color: var(--muted);
}

.probability-label strong {
  color: var(--text);
}

.probability-bar {
  height: 12px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.28);
}

.probability-bar span {
  display: block;
  width: 50%;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  box-shadow: 0 0 22px rgba(95, 231, 255, 0.38);
  transition:
    width 680ms var(--motion-ease),
    box-shadow 360ms ease,
    background 360ms ease;
}

.matrix {
  display: grid;
  grid-template-columns: repeat(2, minmax(86px, 1fr));
  gap: 0.7rem;
  width: min(100%, 430px);
  margin: 0 0 1rem;
  padding: 1rem;
  border-left: 2px solid var(--cyan);
  border-right: 2px solid var(--cyan);
}

.matrix span {
  display: grid;
  min-height: 82px;
  place-items: center;
  padding: 0.55rem;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
  font-size: clamp(1.05rem, 2vw, 1.42rem);
  text-align: center;
  transition:
    background 360ms ease,
    border-color 360ms ease,
    box-shadow 360ms ease,
    transform 360ms var(--motion-ease);
}

.matrix span:nth-child(1),
.matrix span:nth-child(4) {
  border-color: rgba(237, 178, 78, 0.28);
  background: rgba(237, 178, 78, 0.075);
}

.matrix span:nth-child(2),
.matrix span:nth-child(3) {
  border-color: rgba(82, 214, 230, 0.28);
  background: rgba(82, 214, 230, 0.075);
}

.matrix.is-coherence-changing span:nth-child(2),
.matrix.is-coherence-changing span:nth-child(3) {
  animation: coherenceCellPulse 900ms ease both;
}

.matrix.is-diagonal-changing span:nth-child(1),
.matrix.is-diagonal-changing span:nth-child(4) {
  animation: diagonalCellPulse 780ms ease both;
}

.matrix.is-mixing-changing span {
  animation: matrixWholePulse 820ms ease both;
}

@keyframes coherenceCellPulse {
  0%,
  100% {
    box-shadow: inset 0 0 0 rgba(82, 214, 230, 0);
  }
  45% {
    box-shadow: inset 0 0 28px rgba(82, 214, 230, 0.24), 0 0 22px rgba(82, 214, 230, 0.14);
  }
}

@keyframes diagonalCellPulse {
  0%,
  100% {
    transform: translateY(0);
    box-shadow: inset 0 0 0 rgba(237, 178, 78, 0);
  }
  45% {
    transform: translateY(-1px);
    box-shadow: inset 0 0 28px rgba(237, 178, 78, 0.22), 0 0 20px rgba(237, 178, 78, 0.11);
  }
}

@keyframes matrixWholePulse {
  0%,
  100% {
    box-shadow: inset 0 0 0 rgba(148, 136, 247, 0);
  }
  48% {
    box-shadow: inset 0 0 32px rgba(148, 136, 247, 0.18), 0 0 24px rgba(82, 214, 230, 0.1);
  }
}

.dial {
  display: grid;
  width: 152px;
  aspect-ratio: 1;
  margin: 0 auto 1rem;
  place-items: center;
  border-radius: 50%;
  background:
    radial-gradient(circle, rgba(6, 10, 20, 0.96) 0 54%, transparent 55%),
    conic-gradient(var(--cyan) var(--dial-angle, 360deg), rgba(255, 255, 255, 0.1) 0);
  box-shadow: 0 0 34px rgba(95, 231, 255, 0.18);
}

.dial span {
  color: var(--text);
  font-size: 1.55rem;
  font-weight: 820;
}

.purity-readout + .state-type {
  margin-top: 0.8rem;
}

.purity-readout strong {
  color: var(--cyan);
  font-size: 2rem;
}

.state-type strong {
  color: var(--gold);
}

.bloch-stage {
  position: relative;
  display: block;
  width: 100%;
  min-height: 420px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 50% 50%, rgba(95, 231, 255, 0.16), transparent 38%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.05), rgba(255, 255, 255, 0.02));
  isolation: isolate;
  overflow: hidden;
}

.bloch-stage-3d {
  cursor: grab;
  touch-action: none;
}

.bloch-stage-3d:active {
  cursor: grabbing;
}

.bloch-stage canvas {
  position: absolute;
  inset: 0;
  z-index: 1;
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
}

.bloch-hint {
  position: absolute;
  left: 0.75rem;
  right: 0.75rem;
  bottom: 0.75rem;
  z-index: 2;
  padding: 0.58rem 0.72rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  color: rgba(244, 248, 255, 0.78);
  background: rgba(2, 3, 10, 0.56);
  backdrop-filter: blur(12px);
  font-size: 0.78rem;
  text-align: center;
  pointer-events: none;
}

.bloch-hint.is-error {
  border-color: rgba(255, 126, 168, 0.42);
  color: rgba(255, 232, 240, 0.92);
  background: rgba(30, 4, 15, 0.72);
}

.chart-wrap {
  position: relative;
  min-height: 300px;
  padding: 0.7rem 0.4rem 1.7rem 1.5rem;
}

.chart-wrap canvas {
  display: block;
  width: 100%;
  height: 280px;
}

.chart-axis {
  position: absolute;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 720;
}

.y-axis {
  left: 0;
  top: 50%;
  transform: rotate(-90deg) translateX(18%);
  transform-origin: left center;
}

.x-axis {
  right: 0.65rem;
  bottom: 0;
}

.explanation-panel p {
  max-width: 800px;
  color: var(--muted-strong);
  font-size: 1.02rem;
}

.calc-details,
.steps-panel details,
.glossary-grid details {
  margin-top: 0.8rem;
  border: 1px solid rgba(95, 231, 255, 0.16);
  border-radius: var(--radius);
  background: rgba(0, 0, 0, 0.16);
}

.calc-details summary,
.steps-panel summary,
.glossary-grid summary {
  padding: 0.62rem 0.72rem;
  color: var(--cyan);
  cursor: pointer;
  font-weight: 780;
}

.calc-details p,
.steps-panel p,
.glossary-grid p,
.environment-panel p,
.measurement-result,
.challenge-list span {
  color: var(--muted-strong);
}

.calc-details p,
.steps-panel p,
.glossary-grid p {
  margin: 0;
  padding: 0 0.72rem 0.72rem;
  line-height: 1.55;
}

.compare-grid,
.measurement-bars,
.glossary-grid {
  display: grid;
  gap: 0.8rem;
}

.compare-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.compare-grid > div > span {
  display: block;
  margin-bottom: 0.55rem;
  color: var(--muted);
  font-weight: 760;
}

.mini-matrix {
  width: 100%;
  margin-bottom: 0;
  padding: 0.7rem;
}

.mini-matrix span {
  min-height: 56px;
  font-size: 1rem;
}

.environment-visual {
  --environment-intensity: 0.32;
  position: relative;
  min-height: 210px;
  margin-bottom: 0.9rem;
  border: 1px solid rgba(95, 231, 255, 0.16);
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 50% 50%, rgba(95, 231, 255, calc(0.08 + var(--environment-intensity) * 0.22)), transparent 32%),
    linear-gradient(135deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0.015));
  overflow: hidden;
}

.env-node {
  position: absolute;
  left: 50%;
  top: 50%;
  display: grid;
  width: 58px;
  aspect-ratio: 1;
  place-items: center;
  border: 1px solid rgba(95, 231, 255, 0.48);
  border-radius: 50%;
  color: var(--text);
  background: rgba(4, 11, 24, 0.86);
  box-shadow: 0 0 calc(22px + var(--environment-intensity) * 34px) rgba(95, 231, 255, 0.26);
  transform: translate(-50%, -50%);
  font-weight: 860;
}

.env-wave {
  position: absolute;
  inset: 50%;
  width: 72px;
  aspect-ratio: 1;
  border: 1px solid rgba(169, 140, 255, 0.34);
  border-radius: 50%;
  transform: translate(-50%, -50%) scale(calc(1 + var(--environment-intensity)));
  opacity: calc(0.25 + var(--environment-intensity) * 0.55);
}

.env-wave.two {
  border-color: rgba(95, 231, 255, 0.3);
  transform: translate(-50%, -50%) scale(calc(1.55 + var(--environment-intensity) * 1.5));
}

.env-particle {
  position: absolute;
  width: 8px;
  aspect-ratio: 1;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 18px rgba(95, 231, 255, 0.5);
  opacity: calc(0.35 + var(--environment-intensity) * 0.55);
}

.env-particle.p1 { left: 18%; top: 28%; }
.env-particle.p2 { right: 20%; top: 22%; background: var(--violet); }
.env-particle.p3 { left: 26%; bottom: 22%; background: var(--gold); }
.env-particle.p4 { right: 24%; bottom: 28%; }

.measurement-actions,
.compact-actions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 0.72rem;
  width: 100%;
}

.measurement-result {
  min-height: 3rem;
  margin: 0.9rem 0;
}

.measurement-bars {
  grid-template-columns: 1fr;
}

.measurement-bars span {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--muted-strong);
}

.steps-panel details + details {
  margin-top: 0.62rem;
}

.challenge-list {
  display: grid;
  gap: 0.62rem;
}

.challenge-list div {
  display: grid;
  gap: 0.2rem;
  padding: 0.72rem;
  border: 1px solid rgba(255, 255, 255, 0.11);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
}

.challenge-list strong {
  color: var(--text);
}

.challenge-list em {
  color: var(--muted);
  font-style: normal;
  font-weight: 780;
}

.challenge-list div.is-complete {
  border-color: rgba(95, 231, 255, 0.38);
  background: rgba(95, 231, 255, 0.08);
}

.challenge-list div.is-complete em {
  color: var(--cyan);
}

.report-output {
  width: 100%;
  min-height: 260px;
  margin-top: 0.8rem;
  padding: 0.85rem;
  border: 1px solid rgba(255, 255, 255, 0.13);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(3, 7, 18, 0.8);
  resize: vertical;
}

.report-output[hidden],
.print-report {
  display: none;
}

.report-preview {
  display: grid;
  gap: 0.76rem;
  margin-top: 0.9rem;
  color: var(--muted-strong);
}

.report-preview > p {
  padding: 0.9rem;
  border: 1px dashed rgba(95, 231, 255, 0.22);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.04);
}

.report-preview-head {
  padding: 0.9rem;
  border: 1px solid rgba(95, 231, 255, 0.22);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(95, 231, 255, 0.12), rgba(169, 140, 255, 0.08)),
    rgba(0, 0, 0, 0.16);
}

.report-preview-head h3 {
  font-size: 1.12rem;
}

.report-preview-head p {
  margin-top: 0.3rem;
  color: var(--muted-strong);
}

.report-summary-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.48rem;
}

.report-summary-grid span {
  min-width: 0;
  padding: 0.58rem 0.64rem;
  overflow-wrap: anywhere;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.045);
  font-size: 0.88rem;
}

.report-preview-section {
  padding-top: 0.74rem;
}

.report-preview-section h4 {
  margin: 0;
  padding: 0 0.86rem 0.62rem;
  color: var(--cyan);
  font-size: 0.98rem;
}

.report-footer-note {
  padding: 0.85rem;
  border: 0;
  border-left: 3px solid rgba(244, 201, 107, 0.72);
  border-radius: var(--radius);
  color: #fff0c2;
  background: rgba(244, 201, 107, 0.08);
}

.glossary-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.simulator-body[data-mode="beginner"] .advanced-only {
  display: none;
}

.simulator-body[data-mode="beginner"] .calc-details {
  display: none;
}

.page-hero {
  position: relative;
  min-height: 470px;
  padding: 132px 0 70px;
  overflow: hidden;
  isolation: isolate;
  background:
    linear-gradient(90deg, rgba(2, 3, 10, 0.94), rgba(2, 3, 10, 0.56) 58%, rgba(2, 3, 10, 0.86)),
    url("assets/quantum-field.png") center / cover no-repeat;
}

.page-hero::after {
  position: absolute;
  inset: auto 0 0;
  height: 28%;
  content: "";
  background: linear-gradient(to bottom, transparent, var(--bg));
  pointer-events: none;
  z-index: -1;
}

.page-hero-inner {
  display: grid;
  align-content: center;
  min-height: 310px;
}

.page-hero-inner h1 {
  font-size: clamp(2.7rem, 5.6vw, 5.1rem);
}

.page-hero-inner > p:last-child {
  max-width: 780px;
  margin-top: 1.2rem;
  color: #dbe6f3;
  font-size: clamp(1.04rem, 2vw, 1.24rem);
}

.inline-action {
  justify-self: start;
  margin-top: 0.4rem;
}

.feature-grid,
.comparison-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.compact-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.feature-card,
.concept-card,
.comparison-card,
.activity-card,
.info-band {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.085), rgba(255, 255, 255, 0.035));
  box-shadow: var(--shadow);
  backdrop-filter: blur(22px);
  transition:
    transform 420ms var(--motion-ease),
    border-color 420ms ease,
    background 420ms ease,
    box-shadow 420ms ease;
}

.feature-card,
.comparison-card,
.activity-card {
  padding: 1.1rem;
}

.feature-card {
  min-height: 176px;
}

.feature-card span,
.level-heading span {
  color: var(--gold);
  font-size: 0.78rem;
  font-weight: 780;
  text-transform: uppercase;
}

.feature-card h3,
.comparison-card h3 {
  margin-top: 0.75rem;
}

.feature-card p,
.comparison-card p {
  margin-top: 0.68rem;
  font-size: 0.95rem;
}

.hero-observatory-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.98fr) minmax(360px, 0.82fr);
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
}

.hero-lab-visual {
  display: grid;
  gap: 1rem;
  padding: clamp(1rem, 2vw, 1.35rem);
  border: 1px solid rgba(82, 214, 230, 0.18);
  border-radius: var(--radius);
  background:
    linear-gradient(180deg, rgba(13, 20, 38, 0.82), rgba(7, 11, 22, 0.7)),
    rgba(13, 20, 38, 0.68);
  box-shadow: var(--shadow);
}

.hero-lab-visual canvas {
  width: 100%;
  aspect-ratio: 1.28;
  min-height: 280px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius);
  background: rgba(2, 3, 10, 0.46);
}

.hero-dashboard {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.55rem;
}

.hero-dashboard div,
.concept-map article,
.reference-list article {
  border: 1px solid rgba(187, 222, 255, 0.14);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
}

.hero-dashboard div {
  display: grid;
  gap: 0.18rem;
  min-width: 0;
  padding: 0.72rem;
}

.hero-dashboard span,
.channel-table span:first-child,
.reference-list span {
  color: var(--gold);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
  font-size: 0.72rem;
  font-weight: 760;
  text-transform: uppercase;
}

.hero-dashboard strong {
  min-width: 0;
  overflow-wrap: anywhere;
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
  font-size: 0.95rem;
}

.concept-map {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.9rem;
}

.concept-map article {
  display: grid;
  gap: 0.55rem;
  padding: 1rem;
}

.concept-map span {
  color: var(--cyan);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
  font-size: 1.35rem;
  font-weight: 780;
}

.concept-map h3,
.module-card h3,
.channel-card h3 {
  margin-top: 0;
}

.module-card {
  display: block;
  color: inherit;
  text-decoration: none;
  cursor: pointer;
}

.module-card:focus-visible {
  outline: 2px solid rgba(82, 214, 230, 0.75);
  outline-offset: 4px;
}

.principle-band {
  display: grid;
  grid-template-columns: minmax(320px, 0.9fr) minmax(360px, 1.1fr);
  gap: clamp(48px, 7vw, 96px);
  align-items: center;
  padding: clamp(1.25rem, 3vw, 2.1rem);
  border: 1px solid rgba(82, 214, 230, 0.2);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(82, 214, 230, 0.1), rgba(148, 136, 247, 0.07)),
    rgba(13, 20, 38, 0.62);
}

.inline-link {
  position: relative;
  display: inline-flex;
  overflow: hidden;
  width: fit-content;
  margin-top: 0.85rem;
  color: var(--cyan);
  font-size: 0.9rem;
  font-weight: 760;
  transition:
    color 240ms ease,
    transform 240ms var(--motion-ease);
}

.inline-link:hover {
  color: var(--mint);
  transform: translateX(3px);
}

.discreet-note {
  padding: 0.8rem 0.9rem;
  border-left: 2px solid rgba(82, 214, 230, 0.44);
  color: var(--muted-strong);
  background: rgba(255, 255, 255, 0.035);
  font-size: 0.92rem;
}

.simulation-card {
  display: grid;
  transition:
    transform 420ms var(--motion-ease),
    border-color 420ms ease,
    background 420ms ease,
    box-shadow 420ms ease;
  align-content: start;
}

.simulation-card.is-available {
  border-color: rgba(82, 214, 230, 0.32);
}

.simulation-status {
  display: inline-flex;
  width: fit-content;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 780;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.simulation-status.available {
  border: 1px solid rgba(82, 214, 230, 0.35);
  background: rgba(82, 214, 230, 0.1);
  color: var(--cyan);
}

.simulation-status.development {
  border: 1px solid rgba(245, 184, 89, 0.35);
  background: rgba(245, 184, 89, 0.1);
  color: #f5b859;
}

.simulation-card.is-development {
  opacity: 0.72;
  cursor: pointer;
}

.simulation-card.is-development:hover {
  opacity: 0.88;
}

.development-button {
  border-color: rgba(245, 184, 89, 0.35);
  color: #f5b859;
}

.development-toast {
  position: fixed;
  left: 50%;
  bottom: 28px;
  z-index: 100;
  width: max-content;
  max-width: min(520px, calc(100vw - 32px));
  padding: 14px 18px;
  border: 1px solid rgba(82, 214, 230, 0.35);
  border-radius: 999px;
  color: #eef2fb;
  background: rgba(7, 11, 22, 0.88);
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.35);
  backdrop-filter: blur(14px);
  font-size: 13px;
  line-height: 1.4;
  text-align: center;
  opacity: 0;
  pointer-events: none;
  transform: translateX(-50%) translateY(16px);
  transition:
    opacity 260ms ease,
    transform 260ms ease;
}

.development-toast.is-visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.contact-panel {
  display: grid;
  gap: 1.2rem;
  max-width: 820px;
  margin: 0 auto;
}

.contact-email {
  display: grid;
  gap: 0.35rem;
  padding: clamp(1.1rem, 3vw, 1.45rem);
  border: 1px solid rgba(82, 214, 230, 0.22);
  border-radius: var(--premium-radius, var(--radius));
  background: rgba(7, 11, 22, 0.38);
}

.contact-email span {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.contact-email strong {
  color: var(--text);
  font-size: clamp(1.1rem, 3vw, 1.45rem);
  overflow-wrap: anywhere;
}

.contact-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.site-shell {
  width: min(1160px, calc(100% - 40px));
  margin-inline: auto;
}

.instrument-card {
  position: relative;
  min-width: 0;
  padding: clamp(1rem, 2vw, 1.22rem);
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.085), rgba(255, 255, 255, 0.035)),
    rgba(13, 20, 38, 0.72);
  box-shadow: var(--shadow);
  backdrop-filter: blur(22px);
  transition:
    transform 420ms var(--motion-ease),
    border-color 420ms ease,
    background 420ms ease,
    box-shadow 420ms ease;
}

.instrument-card::before {
  position: absolute;
  inset: 0;
  content: "";
  pointer-events: none;
  background:
    linear-gradient(135deg, rgba(82, 214, 230, 0.09), transparent 40%),
    radial-gradient(circle at 92% 0%, rgba(148, 136, 247, 0.12), transparent 15rem);
}

.instrument-card > * {
  position: relative;
}

.feature-card:hover,
.concept-card:hover,
.comparison-card:hover,
.activity-card:hover,
.instrument-card:hover,
.topic-card:hover,
.lab-panel:hover,
.simulation-card:hover {
  transform: translateY(-4px);
  border-color: rgba(82, 214, 230, 0.38);
  background:
    linear-gradient(180deg, rgba(82, 214, 230, 0.105), rgba(148, 136, 247, 0.045)),
    rgba(13, 20, 38, 0.72);
  box-shadow: 0 26px 68px rgba(0, 0, 0, 0.34), 0 0 42px rgba(82, 214, 230, 0.08);
}

.feature-card:hover span,
.instrument-card:hover .section-kicker,
.comparison-card:hover h3,
.activity-card:hover h4 {
  transform: translateY(-1px);
}

.panel-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  align-items: stretch;
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 3.4rem);
}

.section-description {
  max-width: 780px;
  margin-top: 1rem;
  color: var(--muted-strong);
}

.quantum-button {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.78rem 1.1rem;
  border: 1px solid rgba(82, 214, 230, 0.36);
  border-radius: var(--radius);
  color: #031018;
  background: linear-gradient(135deg, var(--cyan), var(--mint));
  font-weight: 760;
  overflow: hidden;
  transition:
    transform 260ms var(--motion-ease),
    border-color 260ms ease,
    box-shadow 260ms ease;
}

.quantum-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 42px rgba(82, 214, 230, 0.18);
}

.formula-box {
  max-width: 100%;
  padding: 0.8rem 0.9rem;
  overflow-x: auto;
  border: 1px solid rgba(82, 214, 230, 0.2);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(2, 3, 10, 0.46);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
  font-size: 0.95rem;
  line-height: 1.6;
  white-space: nowrap;
}

.readout-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.72rem;
  margin-top: 0.9rem;
}

.readout-panel {
  min-width: 0;
  padding: 0.78rem 0.82rem;
  border: 1px solid rgba(187, 222, 255, 0.14);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
}

.readout-panel span {
  display: block;
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 760;
  text-transform: uppercase;
}

.readout-panel strong {
  display: block;
  min-width: 0;
  margin-top: 0.25rem;
  color: var(--text);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
  font-size: clamp(0.95rem, 2vw, 1.15rem);
  overflow-wrap: anywhere;
}

.accent-cyan {
  border-color: rgba(82, 214, 230, 0.26);
}

.accent-violet {
  border-color: rgba(148, 136, 247, 0.28);
}

.accent-amber {
  border-color: rgba(237, 178, 78, 0.3);
}

.quantum-sim-layout {
  display: grid;
  gap: 1.1rem;
}

.quantum-sim-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(320px, 0.8fr);
  gap: 1rem;
  align-items: start;
}

.quantum-sim-grid .controls-panel {
  grid-area: auto;
}

.simulation-stage-card {
  display: grid;
  gap: 0.85rem;
}

.experiment-canvas {
  display: block;
  width: 100%;
  aspect-ratio: 1.75;
  min-height: 360px;
  border: 1px solid rgba(187, 222, 255, 0.14);
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 25% 22%, rgba(82, 214, 230, 0.1), transparent 20rem),
    linear-gradient(180deg, rgba(2, 3, 10, 0.58), rgba(2, 3, 10, 0.82));
}

.compact-readouts {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.button-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.62rem;
}

.toggle-row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.65rem;
  align-items: center;
  min-height: 44px;
  color: var(--muted-strong);
  font-size: 0.94rem;
}

.toggle-row input {
  width: 18px;
  height: 18px;
  accent-color: var(--cyan);
}

.segmented-control {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(72px, 1fr));
  gap: 0.42rem;
}

.segmented-control button {
  min-height: 42px;
  padding: 0.55rem 0.5rem;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: calc(var(--radius) - 2px);
  color: var(--muted-strong);
  background: rgba(255, 255, 255, 0.055);
  cursor: pointer;
  font-weight: 760;
  transition: border-color 180ms ease, background 180ms ease, transform 180ms ease;
}

.segmented-control button:hover,
.segmented-control button.is-active {
  border-color: rgba(82, 214, 230, 0.42);
  color: var(--text);
  background: rgba(82, 214, 230, 0.12);
}

.coincidence-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.48rem;
  margin-top: 0.85rem;
}

.coincidence-grid div {
  padding: 0.68rem 0.58rem;
  border: 1px solid rgba(187, 222, 255, 0.14);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
  text-align: center;
}

.coincidence-grid span {
  display: block;
  color: var(--gold);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
  font-size: 0.74rem;
}

.coincidence-grid strong {
  display: block;
  margin-top: 0.12rem;
  color: var(--text);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
}

.simulation-mini {
  position: relative;
  width: 100%;
  height: 92px;
  margin-bottom: 0.9rem;
  overflow: hidden;
  border: 1px solid rgba(187, 222, 255, 0.14);
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 18% 50%, rgba(82, 214, 230, 0.22), transparent 4rem),
    rgba(2, 3, 10, 0.38);
}

.simulation-mini::before,
.simulation-mini::after,
.simulation-mini span {
  position: absolute;
  content: "";
}

.qubit-mini::before {
  inset: 16px calc(50% - 30px);
  border: 1px solid rgba(82, 214, 230, 0.42);
  border-radius: 50%;
}

.qubit-mini::after {
  left: 50%;
  top: 50%;
  width: 64px;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--amber));
  transform-origin: left center;
  transform: rotate(-28deg);
}

.slit-mini::before {
  left: 38%;
  top: 16px;
  width: 10px;
  height: 60px;
  border-top: 20px solid rgba(237, 178, 78, 0.7);
  border-bottom: 20px solid rgba(237, 178, 78, 0.7);
  background: transparent;
}

.slit-mini::after {
  right: 18px;
  top: 14px;
  width: 2px;
  height: 64px;
  background: rgba(238, 242, 251, 0.28);
}

.slit-mini span {
  left: 45%;
  right: 28px;
  top: 22px;
  height: 46px;
  background:
    repeating-linear-gradient(
      90deg,
      rgba(82, 214, 230, 0.85) 0 3px,
      transparent 3px 10px
    );
  opacity: 0.62;
}

.eraser-mini::before {
  left: 18px;
  top: 42px;
  width: 58px;
  height: 2px;
  background: var(--cyan);
  box-shadow: 72px -22px 0 rgba(148, 136, 247, 0.72), 72px 22px 0 rgba(237, 178, 78, 0.7);
}

.eraser-mini::after {
  right: 20px;
  top: 16px;
  width: 8px;
  height: 60px;
  border-radius: 999px;
  background:
    linear-gradient(var(--cyan) 0 18%, transparent 18% 32%, var(--violet) 32% 50%, transparent 50% 64%, var(--cyan) 64% 82%, transparent 82%);
}

.channel-table {
  display: grid;
  gap: 0.45rem;
  margin: 1.2rem 0 1rem;
}

.channel-table > div {
  display: grid;
  grid-template-columns: 1.1fr 1fr 0.85fr 1.25fr;
  gap: 0.45rem;
}

.channel-table span {
  min-width: 0;
  padding: 0.72rem 0.75rem;
  border: 1px solid rgba(187, 222, 255, 0.14);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
  overflow-wrap: anywhere;
}

.reference-list {
  display: grid;
  gap: 0.8rem;
}

.reference-list article {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.85rem;
  padding: 1rem;
}

.code-sample {
  max-width: 720px;
  margin: 1.2rem auto 0;
  padding: 1rem;
  overflow-x: auto;
  border: 1px solid rgba(187, 222, 255, 0.16);
  border-radius: var(--radius);
  background: rgba(2, 3, 10, 0.62);
  color: var(--text);
  font-family: "IBM Plex Mono", "Cascadia Mono", Consolas, monospace;
}

.comparison-summary {
  color: var(--muted-strong);
}

.comparison-more {
  margin-top: 0.95rem;
  padding: 0;
  overflow: hidden;
  border: 1px solid rgba(154, 166, 198, 0.16);
  border-radius: var(--premium-radius);
  background: rgba(7, 11, 22, 0.24);
}

.comparison-more summary {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 54px;
  padding: 0 14px;
  border: 0;
  border-radius: 0;
  color: var(--text-main);
  background: transparent;
  cursor: pointer;
  font-size: 0.82rem;
  font-weight: 780;
  list-style: none;
  line-height: 1.2;
}

.comparison-more summary::-webkit-details-marker {
  display: none;
}

.comparison-more[open] summary {
  color: var(--accent-strong);
  border-bottom: 1px solid rgba(82, 214, 230, 0.14);
  background: rgba(95, 231, 255, 0.08);
}

.comparison-more-body {
  display: grid;
  gap: 0.72rem;
  margin-top: 0;
  padding: 14px;
}

.comparison-more-body p,
.comparison-more-body .mini-formula {
  margin: 0;
}

.comparison-more-body p strong,
.concept-content p strong {
  color: var(--gold);
}

.channel-card h3 {
  margin-top: 0;
}

.info-band {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(1.4rem, 4vw, 4rem);
  align-items: start;
  padding: clamp(1.25rem, 3vw, 2.2rem);
}

.warning-band {
  border-color: rgba(244, 201, 107, 0.32);
  background:
    linear-gradient(135deg, rgba(244, 201, 107, 0.1), rgba(95, 231, 255, 0.04)),
    rgba(255, 255, 255, 0.035);
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 0.85rem;
}

.footer-nav a {
  color: var(--muted-strong);
  font-size: 0.9rem;
}

.footer-nav a:hover {
  color: var(--cyan);
}

.theory-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  width: 100%;
  max-width: 980px;
  margin-inline: auto;
  margin-bottom: 1.25rem;
}

.theory-tabs button,
.answer-grid button {
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.07);
  cursor: pointer;
  transition: border-color 180ms ease, background 180ms ease, transform 180ms ease;
}

.theory-tabs button {
  min-height: 44px;
  padding: 0.62rem 0.95rem;
  font-weight: 760;
}

.theory-tabs button:hover,
.theory-tabs button.is-active,
.answer-grid button:hover {
  border-color: rgba(95, 231, 255, 0.42);
  background: rgba(95, 231, 255, 0.12);
}

.theory-content {
  width: 100%;
  max-width: 980px;
  margin: 0 auto;
}

.theory-accordion-list {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.theory-accordion-list[hidden] {
  display: none;
}

.concept-card {
  width: 100%;
  min-height: 74px;
  padding: 0;
  overflow: hidden;
  border-color: rgba(187, 222, 255, 0.18);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.09), rgba(95, 231, 255, 0.035)),
    rgba(7, 11, 23, 0.66);
  transition: border-color 180ms ease, background 180ms ease, transform 180ms ease;
}

.concept-card:has(.concept-toggle[aria-expanded="true"]) {
  border-color: rgba(95, 231, 255, 0.34);
  background:
    linear-gradient(180deg, rgba(95, 231, 255, 0.105), rgba(255, 255, 255, 0.04)),
    rgba(7, 11, 23, 0.74);
}

.concept-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  min-height: 74px;
  padding: 1.05rem 1.25rem;
  border: 0;
  color: var(--text);
  background: transparent;
  cursor: pointer;
  font-weight: 780;
  line-height: 1.22;
  text-align: left;
}

.concept-toggle span:first-child {
  min-width: 0;
  overflow-wrap: anywhere;
}

.concept-toggle:hover {
  background: rgba(95, 231, 255, 0.055);
}

.concept-toggle:focus-visible {
  outline: 2px solid rgba(95, 231, 255, 0.78);
  outline-offset: -2px;
}

.concept-card > summary {
  min-height: 72px;
  padding: 1rem 1.05rem;
  color: var(--text);
  cursor: pointer;
  font-weight: 780;
}

.concept-toggle-icon {
  flex: 0 0 auto;
  position: relative;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 1px solid rgba(95, 231, 255, 0.24);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.06);
}

.concept-toggle-icon::before,
.concept-toggle-icon::after {
  position: absolute;
  width: 13px;
  height: 2px;
  content: "";
  border-radius: 999px;
  background: var(--cyan);
  transition: transform 180ms ease, opacity 180ms ease;
}

.concept-toggle-icon::after {
  transform: rotate(90deg);
}

.concept-toggle[aria-expanded="true"] .concept-toggle-icon::after {
  transform: rotate(90deg) scaleX(0);
  opacity: 0;
}

.concept-content {
  display: grid;
  gap: 0.85rem;
  padding: 1rem 1.25rem 1.25rem;
  margin: 0;
  overflow: hidden;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  opacity: 1;
  transform: translateY(0);
  transition:
    max-height 460ms var(--motion-ease),
    opacity 280ms ease,
    transform 360ms var(--motion-ease);
}

.concept-content[hidden] {
  display: none;
}

.concept-card p,
.concept-card .mini-formula {
  margin: 0;
}

.concept-note {
  padding: 0.75rem 0.85rem;
  border: 1px solid rgba(244, 201, 107, 0.18);
  border-radius: var(--radius);
  background: rgba(244, 201, 107, 0.065);
  color: #efe4c3;
  font-size: 0.94rem;
}

.concept-note strong {
  color: var(--gold);
}

@keyframes conceptReveal {
  from {
    opacity: 0;
    transform: translateY(-4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.mini-formula {
  max-width: 100%;
  padding: 0.75rem 0.85rem;
  overflow-x: auto;
  border: 1px solid rgba(95, 231, 255, 0.18);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(0, 0, 0, 0.22);
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 1.08rem;
  white-space: nowrap;
}

.comparison-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.comparison-card {
  display: grid;
  align-content: start;
  min-height: 260px;
}

.mini-bloch {
  position: relative;
  display: grid;
  place-items: center;
  width: min(220px, 100%);
  aspect-ratio: 1;
  margin: 0 auto 1rem;
  border: 1px solid rgba(95, 231, 255, 0.34);
  border-radius: 50%;
  background:
    radial-gradient(circle at 42% 34%, rgba(255, 255, 255, 0.28), transparent 18%),
    radial-gradient(circle at 50% 50%, rgba(95, 231, 255, 0.13), rgba(169, 140, 255, 0.06) 58%, rgba(0, 0, 0, 0.24));
  box-shadow: inset 0 0 42px rgba(95, 231, 255, 0.16), 0 18px 42px rgba(0, 0, 0, 0.26);
}

.mini-bloch::before,
.mini-bloch::after {
  position: absolute;
  content: "";
  background: rgba(255, 255, 255, 0.24);
}

.mini-bloch::before {
  width: 1px;
  height: 78%;
}

.mini-bloch::after {
  width: 78%;
  height: 1px;
}

.mini-bloch span {
  position: absolute;
  z-index: 1;
  display: inline-grid;
  place-items: center;
  min-width: 46px;
  min-height: 34px;
  padding: 0.28rem 0.48rem;
  border: 1px solid rgba(95, 231, 255, 0.28);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(2, 3, 10, 0.72);
  font-weight: 780;
  animation: blochMarkerBreathe 4.8s ease-in-out infinite;
}

.mini-bloch.north span { top: 0.65rem; }
.mini-bloch.south span { bottom: 0.65rem; }
.mini-bloch.x-plus span,
.mini-bloch.surface span { right: 0.65rem; }
.mini-bloch.x-minus span { left: 0.65rem; }
.mini-bloch.y-plus span { inset: auto 0.65rem 50% auto; transform: translateY(50%); }
.mini-bloch.inside span { inset: 50% auto auto 50%; transform: translate(-50%, -50%); }

.visual-matrix {
  width: min(280px, 100%);
  margin: 0;
}

.density-matrix-figure {
  display: flex;
  align-items: center;
  gap: 0.72rem;
  width: 100%;
  margin: 0.95rem 0 0.2rem;
}

.density-matrix-label {
  color: var(--gold);
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 1.18rem;
  font-weight: 780;
  white-space: nowrap;
}

.comparison-card .matrix-caption {
  margin-top: 0.75rem;
  color: var(--muted-strong);
}

.comparison-note {
  max-width: 880px;
  margin: 1.1rem auto 0;
  padding: 0.95rem 1rem;
  border: 1px solid rgba(95, 231, 255, 0.16);
  border-radius: var(--radius);
  color: var(--muted-strong);
  background: rgba(3, 7, 18, 0.34);
}

.faded-matrix span:nth-child(2),
.faded-matrix span:nth-child(3) {
  color: var(--gold);
}

.comparison-card:hover .mini-bloch span {
  border-color: rgba(82, 214, 230, 0.54);
  box-shadow: 0 0 24px rgba(82, 214, 230, 0.14);
}

.comparison-card:hover .visual-matrix span:nth-child(2),
.comparison-card:hover .visual-matrix span:nth-child(3) {
  animation: coherenceCellPulse 900ms ease both;
}

.comparison-card:hover .visual-matrix span:nth-child(1),
.comparison-card:hover .visual-matrix span:nth-child(4) {
  animation: diagonalCellPulse 900ms ease both;
}

@keyframes blochMarkerBreathe {
  0%,
  100% {
    box-shadow: 0 0 0 rgba(82, 214, 230, 0);
  }
  50% {
    box-shadow: 0 0 24px rgba(82, 214, 230, 0.12);
  }
}

.activity-level {
  display: grid;
  gap: 0.9rem;
  margin-top: 1.45rem;
}

.level-heading {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem 0.85rem;
  align-items: baseline;
}

.activity-card {
  display: grid;
  gap: 0.8rem;
}

.activity-card h4 {
  margin: 0;
  color: var(--text);
  font-size: 1.05rem;
}

.activity-card.is-complete {
  border-color: rgba(159, 255, 210, 0.36);
}

.answer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 0.65rem;
}

.answer-grid button {
  min-height: 50px;
  padding: 0.68rem 0.8rem;
  overflow-wrap: anywhere;
}

.answer-grid button.is-correct {
  border-color: rgba(159, 255, 210, 0.68);
  color: #04140f;
  background: linear-gradient(135deg, var(--mint), var(--cyan));
}

.answer-grid button.is-wrong {
  border-color: rgba(255, 126, 168, 0.62);
  background: rgba(255, 126, 168, 0.14);
}

.activity-feedback {
  min-height: 2.2rem;
  padding: 0.75rem 0.85rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
}

.activity-feedback.is-correct {
  border-color: rgba(159, 255, 210, 0.32);
  color: #dfffee;
}

.activity-feedback.is-wrong {
  border-color: rgba(255, 126, 168, 0.34);
  color: #ffd8e4;
}

.progress-pill {
  display: inline-flex;
  align-items: center;
  min-height: 48px;
  padding: 0.78rem 1rem;
  border: 1px solid rgba(95, 231, 255, 0.22);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.07);
  font-weight: 760;
}

.simulator-help-actions {
  margin-top: 1rem;
}

.onboarding-modal {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: rgba(2, 3, 10, 0.72);
  backdrop-filter: blur(10px);
}

.onboarding-modal.is-visible {
  display: flex;
}

.onboarding-modal.is-tour {
  align-items: flex-end;
  justify-content: flex-end;
  background: transparent;
  backdrop-filter: none;
  pointer-events: none;
}

body.tour-active::before {
  position: fixed;
  inset: 0;
  z-index: 45;
  content: "";
  pointer-events: none;
  background: rgba(2, 3, 10, 0.48);
}

.onboarding-card {
  position: relative;
  width: min(520px, calc(100vw - 32px));
  padding: 1.25rem;
  border: 1px solid rgba(95, 231, 255, 0.26);
  border-radius: var(--radius);
  background:
    linear-gradient(145deg, rgba(12, 18, 32, 0.96), rgba(17, 25, 43, 0.92)),
    var(--surface-strong);
  box-shadow: var(--shadow);
  pointer-events: auto;
}

.onboarding-card h2 {
  margin-bottom: 0.75rem;
  font-size: clamp(1.35rem, 3vw, 2rem);
}

.tour-title {
  margin: 0 0 0.55rem;
  color: var(--text);
}

.tour-meta {
  min-height: 1.4rem;
  margin-top: 0.65rem;
  color: var(--gold);
  font-weight: 760;
}

.onboarding-close {
  position: absolute;
  top: 0.7rem;
  right: 0.7rem;
  width: 38px;
  height: 38px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  color: var(--text);
  background: rgba(255, 255, 255, 0.07);
  cursor: pointer;
}

.dont-show {
  display: flex;
  gap: 0.55rem;
  align-items: center;
  margin-top: 1rem;
  color: var(--muted-strong);
  font-size: 0.92rem;
}

.onboarding-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.65rem;
  margin-top: 1rem;
}

.tour-only,
.onboarding-modal.is-tour .intro-only,
.onboarding-modal.is-tour #onboarding-title {
  display: none;
}

.onboarding-modal.is-tour .tour-only {
  display: inline-flex;
}

.tour-highlight {
  position: relative;
  z-index: 55;
  outline: 2px solid rgba(95, 231, 255, 0.92);
  outline-offset: 6px;
  box-shadow: 0 0 0 9999px rgba(2, 3, 10, 0.08), 0 0 38px rgba(95, 231, 255, 0.34);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 980px) {
  .menu-toggle {
    display: inline-block;
  }

  .main-nav {
    position: fixed;
    top: var(--header-height);
    left: 20px;
    right: 20px;
    display: grid;
    gap: 0.2rem;
    padding: 0.55rem;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: var(--radius);
    background: rgba(4, 7, 18, 0.94);
    box-shadow: var(--shadow);
    transform: translateY(-10px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 180ms ease, transform 180ms ease;
  }

  .main-nav.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .main-nav a {
    border-radius: var(--radius);
  }

  .nav-active-pill {
    display: none;
  }

  .main-nav a.is-active,
  .main-nav a[aria-current="page"] {
    border-color: rgba(95, 231, 255, 0.22);
    background: rgba(255, 255, 255, 0.07);
  }

  .split-layout,
  .objective-layout,
  .future-layout,
  .hero-observatory-grid,
  .principle-band,
  .quantum-sim-grid,
  .panel-grid {
    grid-template-columns: 1fr;
  }

  .simulator-guide {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .simulator-main-grid,
  .simulator-results-grid,
  .simulator-support-grid,
  .simulator-decoherence-grid,
  .simulator-learning-grid,
  .simulator-export-grid {
    grid-template-columns: 1fr;
  }

  .lab-grid {
    grid-template-areas:
      "controls controls"
      "ket ket"
      "probabilities matrix"
      "coherence matrix"
      "bloch chart"
      "purity chart"
      "explain explain"
      "compare compare"
      "environment measure"
      "steps steps"
      "challenges report"
      "glossary glossary";
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .topic-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .feature-grid,
  .compact-grid,
  .concept-grid,
  .comparison-grid,
  .concept-map,
  .readout-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .channel-table > div {
    grid-template-columns: 1fr 1fr;
  }

  .info-band {
    grid-template-columns: 1fr;
  }

  .timeline {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .timeline li:nth-child(4n)::after {
    content: "";
  }

  .timeline li:nth-child(2n)::after,
  .timeline li:last-child::after {
    content: none;
  }

  .future-layout .button {
    justify-self: start;
  }

  .development-head {
    grid-template-columns: 1fr;
    align-items: start;
  }
}

@media (max-width: 640px) {
  :root {
    --header-height: 70px;
  }

  .page-shell {
    width: min(100% - 28px, 1160px);
  }

  .brand span:last-child {
    max-width: 210px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .hero,
  .simulator-hero,
  .page-hero {
    min-height: auto;
    padding: 126px 0 76px;
  }

  h1 {
    max-width: 100%;
    font-size: clamp(2.45rem, 13vw, 3.95rem);
    overflow-wrap: anywhere;
  }

  h2 {
    max-width: 100%;
    font-size: clamp(1.8rem, 9vw, 2.75rem);
    overflow-wrap: anywhere;
  }

  .hero-actions,
  .readout-row,
  .readout-grid,
  .hero-metrics,
  .hero-dashboard,
  .simulator-guide,
  .amplitude-grid,
  .compare-grid,
  .glossary-grid,
  .measurement-actions,
  .compact-actions,
  .development-actions,
  .report-summary-grid {
    grid-template-columns: 1fr;
  }

  .concept-map,
  .channel-table > div,
  .button-grid,
  .segmented-control,
  .coincidence-grid {
    grid-template-columns: 1fr;
  }

  .development-panel {
    margin-top: 0.95rem;
  }

  .development-step summary {
    padding-right: 2rem;
  }

  .formula-stack code {
    font-size: 0.92rem;
  }

  .mode-switch {
    grid-auto-flow: row;
    width: 100%;
  }

  .mode-switch button,
  .mode-switch span {
    text-align: center;
  }

  .preset-buttons {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .math-keyboard {
    padding: 0.7rem;
  }

  .math-keyboard-head {
    align-items: stretch;
    flex-direction: column;
  }

  .math-keyboard-head strong {
    text-align: center;
  }

  .math-key-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .math-state-presets {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .math-key-grid button,
  .math-state-presets button {
    min-height: 42px;
    padding-inline: 0.32rem;
  }

  .hero-actions {
    display: grid;
  }

  .button {
    width: 100%;
  }

  .content-band,
  .quote-section,
  .simulator-lab {
    padding: 78px 0;
  }

  .simulator-flow {
    gap: 3rem;
  }

  .simulator-section {
    gap: 1rem;
  }

  .simulator-section-header {
    grid-template-columns: 1fr;
  }

  .simulator-section-index {
    width: 40px;
  }

  .control-group {
    grid-template-columns: 1fr;
  }

  .control-group output,
  .control-group select,
  .control-group input[type="text"],
  .control-group input[type="range"] {
    width: 100%;
  }

  .simulator-accordion-trigger {
    align-items: stretch;
    flex-direction: column;
  }

  .simulator-accordion-trigger em {
    width: 100%;
    text-align: center;
  }

  .theory-tabs {
    display: grid;
    grid-template-columns: 1fr;
  }

  .theory-tabs button {
    min-height: 48px;
  }

  .theory-accordion-list {
    gap: 0.78rem;
  }

  .concept-toggle {
    min-height: 68px;
    padding: 0.95rem 1rem;
  }

  .concept-content {
    padding: 0.95rem 1rem 1rem;
  }

  .mini-formula {
    font-size: 0.98rem;
    overflow-wrap: anywhere;
    white-space: normal;
  }

  .topic-grid,
  .feature-grid,
  .compact-grid,
  .concept-grid,
  .comparison-grid,
  .info-band,
  .timeline,
  .lab-grid,
  .panel-grid,
  .quantum-sim-grid {
    grid-template-columns: 1fr;
  }

  .experiment-canvas {
    min-height: 310px;
    aspect-ratio: 1.05;
  }

  .answer-grid,
  .onboarding-actions {
    grid-template-columns: 1fr;
  }

  .onboarding-modal.is-tour {
    align-items: flex-end;
    justify-content: center;
  }

  .lab-grid {
    grid-template-areas:
      "controls"
      "ket"
      "probabilities"
      "matrix"
      "coherence"
      "purity"
      "bloch"
      "chart"
      "explain"
      "compare"
      "environment"
      "measure"
      "steps"
      "challenges"
      "report"
      "glossary";
  }

  .timeline li::after {
    content: none;
  }

  .bloch-stage {
    min-height: 330px;
  }

  .matrix {
    max-width: none;
  }

  .chart-wrap {
    min-height: 250px;
    padding-left: 1rem;
  }

  .chart-wrap canvas {
    height: 230px;
  }

  .footer-inner {
    display: grid;
  }
}

/* Reference design alignment: Design Physicsqauntumlab.html */
:root {
  --bg: #070b16;
  --bg-deep: #070a14;
  --surface: #0d1426;
  --surface-strong: #0d1426;
  --surface-soft: rgba(13, 20, 38, 0.72);
  --line: rgba(130, 150, 200, 0.16);
  --line-strong: rgba(120, 140, 190, 0.28);
  --text: #eef2fb;
  --muted: #9aa6c6;
  --muted-strong: #c8d2eb;
  --cyan: #52d6e6;
  --cyan-dim: #2c8a96;
  --violet: #9488f7;
  --gold: #edb24e;
  --amber: #edb24e;
  --rose: #ff7ea8;
  --shadow: none;
  --radius: 0px;
  --header-height: 72px;
  --serif: "Newsreader", Georgia, serif;
  --sans: "Inter", system-ui, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
}

body {
  color: var(--text);
  background: var(--bg);
  font-family: var(--sans);
  font-weight: 300;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

body::before {
  z-index: -2;
  background:
    radial-gradient(900px 600px at 78% 18%, rgba(82, 214, 230, 0.07), transparent 60%),
    radial-gradient(800px 700px at 12% 88%, rgba(148, 136, 247, 0.06), transparent 60%),
    linear-gradient(180deg, #070b16 0%, #080d1a 50%, #070a14 100%);
  background-size: auto;
  mask-image: none;
  animation: none;
}

body::after {
  display: none;
}

::selection {
  color: #ffffff;
  background: rgba(82, 214, 230, 0.25);
}

.page-shell,
.site-shell {
  width: min(1200px, calc(100% - 64px));
}

h1,
h2,
h3 {
  font-family: var(--serif);
  font-weight: 300;
  letter-spacing: -0.01em;
}

h1 {
  max-width: 980px;
  font-size: clamp(42px, 6vw, 76px);
  line-height: 1.02;
}

h2,
.section-title,
.page-hero-inner h1,
.simulator-intro h1 {
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1.08;
}

h3 {
  font-size: clamp(20px, 2.2vw, 27px);
}

p,
.section-description,
.hero-copy,
.simulator-intro > p,
.page-hero-inner > p:last-child {
  color: var(--muted);
  font-weight: 300;
}

.eyebrow,
.section-kicker {
  font-family: var(--mono);
  color: var(--cyan);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.28em;
  text-transform: uppercase;
}

.eyebrow::before,
.section-kicker::before {
  display: none;
}

.site-header {
  z-index: 50;
  height: auto;
  min-height: var(--header-height);
  padding: 18px max(32px, calc((100vw - 1200px) / 2));
  border-bottom: 1px solid transparent;
  background: rgba(7, 11, 22, 0.55);
  backdrop-filter: blur(14px);
  transition: border-color 400ms ease, background 400ms ease;
}

.site-header.is-scrolled {
  border-color: var(--line);
  background: rgba(7, 11, 22, 0.82);
}

.brand {
  gap: 12px;
  color: var(--text);
  font-family: var(--mono);
  font-size: 15px;
  font-weight: 400;
  letter-spacing: 0.04em;
}

.brand span:last-child {
  color: var(--cyan);
}

.brand b {
  color: var(--paper);
  font-weight: 500;
}

.brand-mark {
  width: 22px;
  height: 22px;
  border-color: rgba(82, 214, 230, 0.5);
  box-shadow: none;
}

.brand-mark::before {
  inset: 8px 1px;
  border-color: rgba(148, 136, 247, 0.45);
  transform: rotate(0deg) scaleX(1);
}

.brand-mark::after {
  inset: auto;
  left: 10px;
  top: 4px;
  width: 1.3px;
  height: 12px;
  border: 0;
  border-radius: 999px;
  background: var(--cyan);
  box-shadow: 4px -2px 0 1px var(--amber), 0 7px 0 1px var(--cyan);
  transform: rotate(45deg);
  transform-origin: center;
}

.main-nav {
  gap: 30px;
}

.main-nav a {
  min-height: auto;
  padding: 4px 0;
  border: 0;
  border-radius: 0;
  color: var(--muted);
  background: transparent;
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  transition: color 250ms ease;
}

.main-nav a::after {
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 1px;
  content: "";
  background: var(--cyan);
  transition: width 300ms ease;
}

.main-nav a:hover,
.main-nav a.is-active,
.main-nav a[aria-current="page"] {
  color: var(--text);
  background: transparent;
}

.main-nav a:hover::after,
.main-nav a.is-active::after,
.main-nav a[aria-current="page"]::after {
  width: 100%;
}

.nav-active-pill {
  height: 1px !important;
  border: 0;
  border-radius: 0;
  background: var(--cyan);
  box-shadow: none;
  transition:
    transform 520ms cubic-bezier(0.22, 1, 0.36, 1),
    width 520ms cubic-bezier(0.22, 1, 0.36, 1),
    opacity 300ms ease;
}

.menu-toggle {
  border: 0;
  background: transparent;
}

.menu-toggle span {
  height: 1.5px;
}

.hero,
.simulator-hero,
.page-hero {
  min-height: 100vh;
  padding: 120px 0 60px;
  background: transparent;
}

.simulator-hero,
.page-hero {
  min-height: min(620px, 82svh);
}

.hero-observatory-grid {
  grid-template-columns: 1.05fr 1fr;
  gap: 40px;
}

.hero-copy {
  max-width: 46ch;
  margin-top: 26px;
  margin-bottom: 38px;
  font-size: clamp(16px, 1.5vw, 18.5px);
  line-height: 1.7;
}

.hero-lab-visual,
.topic-card,
.formula-panel,
.quote-block,
.lab-panel,
.feature-card,
.concept-card,
.comparison-card,
.activity-card,
.instrument-card,
.simulation-card,
.info-band,
.visual-matrix,
.mini-formula,
.formula-box,
.code-sample,
.channel-table span,
.activity-feedback,
.progress-pill,
.warning-band,
.simulator-inline-accordion,
.onboarding-card {
  border: 1px solid var(--line);
  border-radius: 0;
  background: var(--surface);
  box-shadow: none;
  backdrop-filter: none;
}

.instrument-card::before,
.lab-panel::before,
.hero-lab-visual::before {
  background:
    linear-gradient(135deg, rgba(82, 214, 230, 0.055), transparent 42%),
    radial-gradient(circle at 92% 0%, rgba(148, 136, 247, 0.08), transparent 15rem);
}

.feature-card,
.comparison-card,
.activity-card,
.instrument-card,
.simulation-card,
.lab-panel {
  position: relative;
  overflow: hidden;
}

.feature-card::after,
.comparison-card::after,
.activity-card::after,
.instrument-card::after,
.simulation-card::after,
.lab-panel::after {
  position: absolute;
  left: 0;
  top: 0;
  width: 0;
  height: 2px;
  content: "";
  pointer-events: none;
  background: var(--cyan);
  transition: width 450ms ease;
}

.feature-card:hover,
.concept-card:hover,
.comparison-card:hover,
.activity-card:hover,
.instrument-card:hover,
.topic-card:hover,
.lab-panel:hover,
.simulation-card:hover {
  transform: translateY(-4px);
  border-color: rgba(120, 140, 190, 0.28);
  background: var(--surface);
  box-shadow: none;
}

.feature-card:hover::after,
.comparison-card:hover::after,
.activity-card:hover::after,
.instrument-card:hover::after,
.simulation-card:hover::after,
.lab-panel:hover::after {
  width: 100%;
}

.feature-card span,
.level-heading span,
.mod .tag,
.matrix-caption,
.data-readout span,
.coincidence-grid span {
  font-family: var(--mono);
}

.feature-card h3,
.comparison-card h3,
.activity-card h4 {
  font-family: var(--serif);
  font-weight: 400;
}

.button,
.mini-button,
.preset-button,
.quantum-button,
.segmented-control button,
.theory-tabs button,
.answer-grid button,
.mode-switch button,
.math-key-grid button,
.math-state-presets button,
.onboarding-close {
  border: 1px solid var(--line);
  border-radius: 0;
  font-family: var(--mono);
  font-size: 12.5px;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition:
    transform 350ms ease,
    border-color 350ms ease,
    background 350ms ease,
    color 350ms ease,
    box-shadow 350ms ease;
}

.button.primary,
.quantum-button,
.answer-grid button.is-correct {
  border-color: var(--cyan);
  color: #04222a;
  background: var(--cyan);
  font-weight: 500;
  box-shadow: none;
}

.button.primary:hover,
.quantum-button:hover,
.answer-grid button.is-correct:hover {
  border-color: #6fe2f0;
  background: #6fe2f0;
  transform: translateY(-2px);
}

.button.secondary,
.mini-button,
.preset-button,
.segmented-control button,
.theory-tabs button,
.answer-grid button,
.mode-switch button,
.math-key-grid button,
.math-state-presets button {
  color: var(--text);
  background: transparent;
}

.button.secondary:hover,
.mini-button:hover,
.preset-button:hover,
.segmented-control button:hover,
.segmented-control button.is-active,
.theory-tabs button:hover,
.theory-tabs button.is-active,
.answer-grid button:hover,
.mode-switch button:hover,
.mode-switch button.is-active,
.math-key-grid button:hover,
.math-state-presets button:hover,
.math-state-presets button.is-active {
  border-color: var(--cyan);
  color: var(--cyan);
  background: transparent;
  box-shadow: none;
}

.inline-link,
.simulation-card .go {
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.content-band,
.quote-section,
.simulator-lab {
  padding: 110px 0;
}

.content-band.darker,
.simulator-lab {
  background: transparent;
}

.section-heading {
  max-width: 62ch;
  margin-bottom: 56px;
}

.concept-map,
.module-grid,
.feature-grid,
.comparison-grid,
.panel-grid,
.simulator-guide,
.reference-list {
  gap: 18px;
}

.concept-map article {
  border-color: var(--line);
  background: var(--surface);
}

.concept-map article:hover {
  background: rgba(82, 214, 230, 0.04);
}

.principle-band,
.band-like,
.future-band {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.site-footer {
  padding: 70px 0 50px;
  background: transparent;
}

.simulator-top-back {
  position: fixed;
  top: calc(var(--header-height) + 18px);
  left: 24px;
  z-index: 49;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  width: fit-content;
  margin-bottom: 0;
  padding: 10px 14px;
  border: 1px solid rgba(82, 214, 230, 0.35);
  border-radius: 999px;
  background: rgba(7, 11, 22, 0.55);
  backdrop-filter: blur(12px);
  color: #eef2fb;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-decoration: none;
  text-transform: uppercase;
  animation: topBackEnter 600ms cubic-bezier(0.22, 1, 0.36, 1) both;
  transition:
    transform 300ms cubic-bezier(0.22, 1, 0.36, 1),
    border-color 300ms ease,
    background 300ms ease,
    color 300ms ease;
}

.simulator-top-back:hover {
  transform: translateX(-2px);
  border-color: rgba(82, 214, 230, 0.7);
  background: rgba(13, 20, 38, 0.85);
  color: #52d6e6;
}

.simulator-top-back:active {
  transform: scale(0.98);
}

.simulator-top-back:focus-visible {
  outline: 2px solid rgba(82, 214, 230, 0.75);
  outline-offset: 4px;
}

@keyframes topBackEnter {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.simulation-back-floating {
  position: fixed;
  left: 24px;
  bottom: 24px;
  z-index: 80;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border: 1px solid rgba(82, 214, 230, 0.35);
  border-radius: 999px;
  background: rgba(7, 11, 22, 0.72);
  backdrop-filter: blur(14px);
  color: #eef2fb;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  text-decoration: none;
  text-transform: uppercase;
  box-shadow: 0 14px 40px rgba(0, 0, 0, 0.28);
  animation: floatingBackEnter 650ms cubic-bezier(0.22, 1, 0.36, 1) both;
  transition:
    transform 300ms cubic-bezier(0.22, 1, 0.36, 1),
    border-color 300ms ease,
    background 300ms ease,
    opacity 300ms ease;
}

.simulation-back-floating:hover {
  transform: translateY(-2px);
  border-color: rgba(82, 214, 230, 0.65);
  background: rgba(13, 20, 38, 0.88);
}

.simulation-back-floating:active {
  transform: scale(0.98);
}

.simulation-back-floating:focus-visible {
  outline: 2px solid rgba(82, 214, 230, 0.75);
  outline-offset: 4px;
}

@keyframes floatingBackEnter {
  from {
    opacity: 0;
    transform: translateY(12px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 640px) {
  .simulator-top-back {
    top: calc(var(--header-height) + 10px);
    left: 16px;
    padding: 9px 12px;
    font-size: 10.5px;
  }

  .simulation-back-floating {
    left: 16px;
    bottom: 16px;
    padding: 10px 13px;
    font-size: 11px;
  }
}

.footer-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 30px;
  align-items: start;
  padding-bottom: 0;
  font-size: 0.92rem;
}

.footer-inner > p:first-child,
.footer-nav {
  padding-bottom: 48px;
  border-bottom: 1px solid var(--line);
}

.footer-inner > p:first-child {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.02em;
}

.footer-nav {
  justify-content: flex-end;
  gap: 28px;
}

.footer-nav a {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12.5px;
  transition: color 250ms ease;
}

.footer-nav a:hover {
  color: var(--cyan);
}

@media (max-width: 980px) {
  .page-shell,
  .site-shell {
    width: min(100% - 44px, 1200px);
  }

  .site-header {
    padding: 18px 22px;
  }

  .main-nav {
    top: var(--header-height);
    left: 0;
    right: 0;
    gap: 0;
    padding: 8px 0;
    border-right: 0;
    border-left: 0;
    border-color: var(--line);
    border-radius: 0;
    background: rgba(7, 11, 22, 0.97);
  }

  .main-nav a {
    padding: 15px 32px;
    border-bottom: 1px solid rgba(120, 140, 190, 0.13);
  }

  .main-nav a::after {
    display: none;
  }

  .hero,
  .simulator-hero,
  .page-hero {
    min-height: auto;
    padding-top: 110px;
  }

  .hero-observatory-grid {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .hero-lab-visual {
    order: -1;
  }

  .footer-inner {
    grid-template-columns: 1fr;
  }

  .footer-nav {
    justify-content: flex-start;
  }
}

@media (max-width: 560px) {
  .page-shell,
  .site-shell {
    width: min(100% - 44px, 1200px);
  }

  .content-band,
  .quote-section,
  .simulator-lab {
    padding: 80px 0;
  }
}

@media print {
  @page {
    margin: 18mm;
  }

  *,
  *::before,
  *::after {
    box-shadow: none !important;
    text-shadow: none !important;
  }

  html,
  body {
    color: #111827 !important;
    background: #ffffff !important;
  }

  body::before,
  body::after,
  .simulator-top-back,
  .simulation-back-floating,
  .site-header,
  .simulator-hero,
  .particle-canvas,
  .controls-panel,
  .probability-panel,
  .matrix-panel,
  .coherence-panel,
  .purity-panel,
  .bloch-panel,
  .chart-panel,
  .explanation-panel,
  .compare-panel,
  .environment-panel,
  .measurement-panel,
  .steps-panel,
  .challenges-panel,
  .glossary-panel,
  .development-actions,
  .state-actions,
  .preset-buttons,
  .report-preview,
  .report-output {
    display: none !important;
  }

  main,
  .simulator-lab,
  .page-shell,
  .lab-grid,
  .report-panel {
    display: block !important;
    width: 100% !important;
    max-width: none !important;
    margin: 0 !important;
    padding: 0 !important;
    background: transparent !important;
    border: 0 !important;
  }

  .lab-panel:not(.report-panel),
  .report-panel > :not(.print-report) {
    display: none !important;
  }

  .print-report {
    display: block !important;
    color: #111827 !important;
    background: #ffffff !important;
    font-family: Georgia, "Times New Roman", serif;
  }

  .print-report h1,
  .print-report h2,
  .print-report p,
  .print-report li {
    color: #111827 !important;
  }

  .print-report h1 {
    margin: 0 0 0.35rem;
    font-size: 1.65rem;
  }

  .print-subtitle {
    margin-bottom: 1rem;
    color: #374151 !important;
  }

  .print-report article {
    break-inside: avoid;
    margin-top: 1rem;
    padding-top: 0.8rem;
    border-top: 1px solid #d1d5db;
  }

  .print-report h2 {
    margin: 0 0 0.45rem;
    font-size: 1.05rem;
  }

  .print-report ul {
    margin: 0 0 1rem 1.1rem;
    padding: 0;
  }

  .print-report .formula-stack {
    padding: 0;
  }

.print-report .formula-stack code {
    margin-bottom: 0.35rem;
    color: #111827;
    background: #f3f4f6;
    border-color: #d1d5db;
    white-space: pre-wrap;
  }

  .print-footer-note {
    margin-top: 1.2rem;
    font-style: italic;
  }
}

@keyframes selectedControlPulse {
  0% {
    box-shadow: 0 0 0 rgba(82, 214, 230, 0);
  }
  45% {
    box-shadow: 0 0 0 4px rgba(82, 214, 230, 0.1), 0 18px 36px rgba(82, 214, 230, 0.12);
  }
  100% {
    box-shadow: 0 12px 26px rgba(95, 231, 255, 0.12);
  }
}

@keyframes valuePulse {
  0% {
    box-shadow: 0 0 0 rgba(82, 214, 230, 0);
  }
  45% {
    box-shadow: inset 0 0 24px rgba(82, 214, 230, 0.16), 0 0 28px rgba(82, 214, 230, 0.1);
  }
  100% {
    box-shadow: 0 0 0 rgba(82, 214, 230, 0);
  }
}

@keyframes correctPulse {
  0%,
  100% {
    box-shadow: var(--shadow);
  }
  45% {
    box-shadow: 0 24px 62px rgba(0, 0, 0, 0.34), 0 0 36px rgba(159, 255, 210, 0.16);
  }
}

@keyframes wrongPulse {
  0%,
  100% {
    box-shadow: var(--shadow);
  }
  45% {
    box-shadow: 0 24px 62px rgba(0, 0, 0, 0.34), 0 0 34px rgba(255, 126, 168, 0.14);
  }
}

@keyframes feedbackReveal {
  from {
    opacity: 0;
    transform: translateY(6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.activity-card.answer-correct {
  animation: correctPulse 720ms var(--motion-ease) both;
}

.activity-card.answer-wrong {
  animation: wrongPulse 720ms var(--motion-ease) both;
}

.activity-feedback.feedback-pulse {
  animation: feedbackReveal 340ms var(--motion-ease) both;
}

.formula-box,
.mini-formula,
.density-matrix-figure,
.matrix {
  animation: formulaSettle 720ms var(--motion-ease) both;
}

@keyframes formulaSettle {
  from {
    opacity: 0;
    transform: translateY(8px);
    box-shadow: 0 0 0 rgba(82, 214, 230, 0);
  }
  52% {
    box-shadow: 0 0 26px rgba(82, 214, 230, 0.1);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.simulation-stage-card {
  isolation: isolate;
}

.simulation-stage-card::after {
  position: absolute;
  inset: 1rem;
  z-index: 0;
  content: "";
  pointer-events: none;
  border: 1px solid rgba(82, 214, 230, 0.1);
  border-radius: var(--radius);
  opacity: 0.42;
  animation: labBreath 4.8s ease-in-out infinite;
}

.simulation-stage-card > * {
  z-index: 1;
}

@keyframes labBreath {
  0%,
  100% {
    opacity: 0.25;
    transform: scale(1);
  }
  50% {
    opacity: 0.56;
    transform: scale(1.006);
  }
}

/* Premium UI polish: visual-only refinement layer. */
:root {
  --accent: #52d6e6;
  --accent-strong: #6ff3ff;
  --accent-dark-text: #04161d;
  --text-main: #eef2fb;
  --text-muted: #aab6d6;
  --text-dim: #7f8bad;
  --premium-panel: rgba(30, 41, 59, 0.58);
  --premium-panel-deep: rgba(15, 23, 42, 0.78);
  --premium-line: rgba(255, 255, 255, 0.1);
  --premium-line-strong: rgba(82, 214, 230, 0.42);
  --premium-radius: 8px;
  --premium-shadow: 0 18px 55px rgba(0, 0, 0, 0.22);
  --premium-shadow-hover: 0 22px 60px rgba(0, 0, 0, 0.3);
}

body {
  color: var(--text-main);
  line-height: 1.65;
}

p,
li {
  color: var(--text-muted);
  line-height: 1.75;
}

h1,
h2,
h3 {
  color: var(--text-main);
}

h1 {
  font-size: clamp(44px, 6vw, 78px);
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.03em;
}

.page-hero-inner h1,
.simulator-intro h1 {
  font-size: clamp(44px, 6vw, 78px);
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.03em;
}

h2,
.section-title,
h2.section-title {
  font-size: clamp(30px, 4vw, 48px);
  font-weight: 500;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

h3,
.feature-card h3,
.comparison-card h3,
.activity-card h4,
.level-heading h3 {
  font-size: clamp(20px, 2vw, 28px);
  font-weight: 600;
  line-height: 1.2;
}

.page-hero-inner > p,
.simulator-intro > p,
.section-heading > p,
.quote-block p,
.project-card p,
.project-grid p,
.timeline p,
.concept-card p,
.theory-content p,
.comparison-card p,
.activity-card p,
.lab-panel p,
.instrument-card p,
.simulation-card p,
.info-band p,
.formula-caption,
.discreet-note,
.reference-list p {
  max-width: 760px;
}

main p:not(.eyebrow):not(.section-kicker):not(.formula-caption) {
  max-width: 760px;
}

.page-hero-inner > p,
.section-heading > p,
.quote-block p {
  margin-right: auto;
  margin-left: auto;
}

.section-heading {
  margin-bottom: clamp(32px, 5vw, 56px);
}

.content-band,
.quote-section,
.simulator-lab {
  padding-block: clamp(72px, 9vw, 120px);
}

.feature-grid,
.comparison-grid,
.panel-grid,
.module-grid,
.simulation-grid,
.reference-list,
.concept-map,
.simulator-guide,
.simulator-main-grid,
.simulator-results-grid,
.simulator-learning-grid,
.simulator-export-grid,
.quantum-sim-grid,
.readout-grid,
.activity-level {
  gap: clamp(20px, 2.5vw, 28px);
}

.simulator-flow {
  gap: clamp(48px, 7vw, 84px);
}

.simulator-section + .simulator-section {
  margin-top: clamp(56px, 7vw, 88px);
}

.simulator-section-header {
  margin-bottom: clamp(28px, 4vw, 44px);
}

.simulator-section-header h2,
.section-heading h2 {
  max-width: 820px;
}

.panel-heading {
  margin-bottom: clamp(18px, 2.4vw, 28px);
}

.panel-heading h2,
.lab-panel h2,
.instrument-card h2,
.report-panel h2,
.glossary-panel h2,
.controls-panel h3,
.control-cluster h3,
.comparison-card h3,
.simulation-card h3,
.feature-card h3 {
  font-size: clamp(21px, 2.2vw, 30px);
  line-height: 1.15;
  letter-spacing: -0.01em;
}

.activity-card h4,
.concept-toggle strong,
.simulator-accordion-trigger strong {
  font-size: clamp(18px, 1.6vw, 23px);
  line-height: 1.25;
}

.hero-lab-visual,
.topic-card,
.formula-panel,
.quote-block,
.lab-panel,
.feature-card,
.concept-card,
.comparison-card,
.activity-card,
.instrument-card,
.simulation-card,
.info-band,
.visual-matrix,
.mini-formula,
.formula-box,
.code-sample,
.activity-feedback,
.progress-pill,
.warning-band,
.simulator-inline-accordion,
.onboarding-card,
.report-preview,
.density-matrix-figure,
.reference-list article {
  border: 1px solid var(--premium-line);
  border-radius: var(--premium-radius);
  background: linear-gradient(180deg, rgba(30, 41, 59, 0.66), rgba(15, 23, 42, 0.74));
  box-shadow: var(--premium-shadow);
}

.feature-card,
.concept-card,
.comparison-card,
.activity-card,
.instrument-card,
.simulation-card,
.lab-panel,
.topic-card {
  padding: clamp(22px, 2.4vw, 32px);
}

.module-card,
.simulation-card.is-available {
  cursor: pointer;
}

.feature-card:hover,
.concept-card:hover,
.comparison-card:hover,
.activity-card:hover,
.instrument-card:hover,
.topic-card:hover,
.lab-panel:hover,
.simulation-card:hover,
.module-card:focus-visible {
  transform: translateY(-4px);
  border-color: var(--premium-line-strong);
  box-shadow: var(--premium-shadow-hover);
}

.feature-card::after,
.comparison-card::after,
.activity-card::after,
.instrument-card::after,
.simulation-card::after,
.lab-panel::after {
  height: 3px;
  background: linear-gradient(90deg, var(--accent), rgba(148, 136, 247, 0.82));
}

.bloch-panel,
.simulation-stage-card,
.chart-panel,
.hero-lab-visual {
  border-color: rgba(82, 214, 230, 0.24);
  background:
    radial-gradient(circle at 78% 12%, rgba(82, 214, 230, 0.08), transparent 18rem),
    linear-gradient(180deg, rgba(30, 41, 59, 0.72), rgba(15, 23, 42, 0.78));
}

.controls-panel,
.measurement-panel,
.development-panel,
.report-panel,
.glossary-panel {
  background: linear-gradient(180deg, rgba(17, 24, 39, 0.82), rgba(15, 23, 42, 0.8));
}

.readout-panel,
.data-readout,
.amplitude-grid > div,
.purity-readout,
.state-type,
.probability-label,
.coincidence-grid div,
.challenge-list div {
  border: 1px solid rgba(154, 166, 198, 0.14);
  border-radius: var(--premium-radius);
  background: rgba(7, 11, 22, 0.42);
}

.readout-panel strong,
.data-readout strong,
.amplitude-grid strong,
.purity-readout strong,
.state-type strong,
.probability-label strong,
.hero-dashboard strong,
.hero-metrics strong {
  color: var(--text-main);
  font-weight: 700;
}

.control-cluster,
.control-group,
.state-actions,
.development-actions,
.compact-actions,
.button-grid,
.preset-buttons,
.segmented-control,
.view-tabs,
.simulation-view-tabs,
.math-state-presets {
  gap: 12px;
}

.control-cluster {
  padding: clamp(16px, 1.6vw, 22px);
  border: 1px solid rgba(154, 166, 198, 0.12);
  border-radius: var(--premium-radius);
  background: rgba(7, 11, 22, 0.26);
}

.control-group {
  padding: 12px;
  border: 1px solid rgba(154, 166, 198, 0.12);
  border-radius: var(--premium-radius);
  background: rgba(7, 11, 22, 0.26);
}

.control-group span,
.control-group output,
.pdf-mode-field span,
.readout-panel span,
.data-readout span,
.coincidence-grid span,
.matrix-caption,
.formula-caption,
.progress-pill {
  color: var(--text-dim);
}

.button-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(132px, 1fr));
}

.state-actions,
.development-actions,
.compact-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
}

.preset-buttons,
.answer-grid,
.math-state-presets,
.segmented-control,
.view-tabs,
.simulation-view-tabs,
.theory-tabs,
.mode-switch {
  align-items: stretch;
}

.main-nav a {
  color: rgba(238, 242, 251, 0.58);
  opacity: 0.82;
  transition:
    color 240ms ease,
    opacity 240ms ease,
    background 240ms ease;
}

.main-nav a:hover {
  color: rgba(238, 242, 251, 0.95);
  opacity: 1;
}

.main-nav a[aria-current="page"],
.main-nav a.is-active {
  color: var(--text-main);
  opacity: 1;
}

.main-nav a[aria-current="page"]::after,
.main-nav a.is-active::after {
  height: 2px;
  opacity: 1;
  background: var(--accent);
}

.nav-active-pill {
  height: 2px !important;
  background: var(--accent);
  box-shadow: 0 0 18px rgba(82, 214, 230, 0.42);
}

.button.primary,
.button.cta-primary,
.primary-action,
.cta-primary,
.simulation-card .button.primary,
.inline-action.button.primary,
.state-actions .mini-button:not(.ghost),
.development-actions .mini-button:not(.ghost),
.compact-actions .mini-button:not(.ghost) {
  border: 1px solid rgba(111, 243, 255, 0.9);
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: var(--accent-dark-text);
  font-weight: 800;
  box-shadow: 0 14px 40px rgba(82, 214, 230, 0.18);
}

.button.primary:hover,
.button.cta-primary:hover,
.primary-action:hover,
.cta-primary:hover,
.simulation-card .button.primary:hover,
.inline-action.button.primary:hover,
.state-actions .mini-button:not(.ghost):hover,
.development-actions .mini-button:not(.ghost):hover,
.compact-actions .mini-button:not(.ghost):hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 55px rgba(82, 214, 230, 0.28);
}

.button.secondary,
.mini-button.ghost,
.simulator-accordion-trigger,
.simulator-inline-accordion-trigger {
  border-color: rgba(154, 166, 198, 0.2);
  background: rgba(15, 23, 42, 0.7);
  color: var(--text-main);
}

.button,
.mini-button,
.preset-button,
.answer-grid button,
.math-key-grid button,
.math-state-presets button,
.theory-tabs button,
.mode-switch button,
.segmented-control button,
.view-tabs button,
.simulation-view-tabs button,
.simulator-accordion-trigger,
.simulator-inline-accordion-trigger {
  min-height: 42px;
}

.inline-link,
.simulation-card .go {
  color: var(--accent-strong);
  font-weight: 800;
}

input:not([type="range"]):not([type="checkbox"]):not([type="radio"]),
select,
textarea {
  border: 1px solid rgba(154, 166, 198, 0.24);
  border-radius: var(--premium-radius);
  background: rgba(7, 11, 22, 0.72);
  color: var(--text-main);
  font: inherit;
  padding: 12px 14px;
  transition:
    border-color 240ms ease,
    box-shadow 240ms ease,
    background 240ms ease;
}

input:not([type="range"]):not([type="checkbox"]):not([type="radio"]):hover,
select:hover,
textarea:hover {
  border-color: rgba(82, 214, 230, 0.45);
}

input:not([type="range"]):not([type="checkbox"]):not([type="radio"]):focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: rgba(82, 214, 230, 0.85);
  box-shadow: 0 0 0 4px rgba(82, 214, 230, 0.12);
}

input[type="checkbox"],
input[type="radio"] {
  accent-color: var(--accent);
}

input[type="range"] {
  accent-color: var(--accent);
}

input[type="range"]::-webkit-slider-runnable-track {
  height: 8px;
  border-radius: 999px;
  background: linear-gradient(90deg, rgba(82, 214, 230, 0.5), rgba(148, 136, 247, 0.36));
}

input[type="range"]::-webkit-slider-thumb {
  width: 20px;
  height: 20px;
  margin-top: -6px;
  border: 2px solid rgba(238, 242, 251, 0.9);
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 5px rgba(82, 214, 230, 0.14);
}

.preset-button,
.answer-grid button,
.math-key-grid button,
.math-state-presets button,
.theory-tabs button,
.mode-switch button,
.mini-button,
.segmented-control button,
.view-tabs button,
.simulation-view-tabs button {
  border: 1px solid rgba(154, 166, 198, 0.24);
  border-radius: var(--premium-radius);
  background: rgba(15, 23, 42, 0.75);
  color: var(--text-main);
  padding: 11px 14px;
  transition:
    transform 220ms ease,
    border-color 220ms ease,
    background 220ms ease,
    color 220ms ease,
    box-shadow 220ms ease;
}

.preset-button:hover,
.answer-grid button:hover,
.math-key-grid button:hover,
.math-state-presets button:hover,
.theory-tabs button:hover,
.mode-switch button:hover,
.mini-button:hover,
.segmented-control button:hover,
.view-tabs button:hover,
.simulation-view-tabs button:hover {
  transform: translateY(-1px);
  border-color: rgba(82, 214, 230, 0.55);
  background: rgba(82, 214, 230, 0.09);
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.16);
}

.preset-button.is-active,
.answer-grid button.is-selected,
.theory-tabs button.is-active,
.mode-switch button.is-active,
.segmented-control button.is-active,
.view-tabs button.is-active,
.simulation-view-tabs button.is-active,
button[aria-selected="true"] {
  border-color: rgba(82, 214, 230, 0.85);
  background: rgba(82, 214, 230, 0.16);
  color: var(--accent-strong);
}

.math-keyboard {
  padding: 16px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--premium-radius);
  background: rgba(15, 23, 42, 0.62);
}

.math-key-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(54px, 1fr));
  gap: 8px;
}

.math-key-grid button {
  min-height: 40px;
  font-family: var(--mono);
  font-size: 12px;
}

.math-state-presets {
  gap: 8px;
}

.answer-grid {
  gap: 10px;
}

.activity-feedback {
  color: var(--text-muted);
}

.concept-toggle {
  border-radius: var(--premium-radius);
}

.concept-card {
  overflow: hidden;
}

.concept-toggle,
details summary,
.comparison-more summary,
.calc-details summary,
.glossary-grid summary {
  cursor: pointer;
  color: var(--text-main);
}

details,
.comparison-more,
.calc-details,
.glossary-grid details {
  border: 1px solid rgba(154, 166, 198, 0.12);
  border-radius: var(--premium-radius);
  background: rgba(7, 11, 22, 0.24);
}

details summary {
  padding: 12px 14px;
  border-radius: var(--premium-radius);
  transition:
    color 220ms ease,
    background 220ms ease,
    border-color 220ms ease;
}

details summary:hover {
  color: var(--accent-strong);
  background: rgba(82, 214, 230, 0.06);
}

details[open] summary {
  color: var(--accent-strong);
  border-bottom: 1px solid rgba(82, 214, 230, 0.14);
}

details > :not(summary) {
  margin-right: 14px;
  margin-left: 14px;
}

details > :last-child {
  margin-bottom: 14px;
}

.comparison-more > summary {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 54px;
  padding: 0 14px;
  border: 0;
  border-radius: 0;
  background: transparent;
  line-height: 1.2;
  list-style: none;
}

.comparison-more > summary:hover {
  color: var(--accent-strong);
  background: rgba(82, 214, 230, 0.06);
}

.comparison-more[open] > summary {
  color: var(--accent-strong);
  border-bottom: 1px solid rgba(82, 214, 230, 0.14);
  background: rgba(95, 231, 255, 0.08);
}

.comparison-more > .comparison-more-body {
  margin: 0;
  padding: 14px;
}

.concept-content {
  color: var(--text-muted);
}

.matrix,
.mini-matrix,
.visual-matrix {
  border-color: rgba(82, 214, 230, 0.18);
  background: rgba(7, 11, 22, 0.5);
}

.formula-box,
.mini-formula,
.formula-stack code,
.code-sample {
  border-color: rgba(82, 214, 230, 0.18);
  background: rgba(7, 11, 22, 0.58);
}

.experiment-canvas,
[data-bloch-canvas],
[data-decoherence-chart] {
  max-width: 100%;
}

.chart-wrap,
.bloch-stage,
.simulation-stage-card {
  overflow: hidden;
  border-radius: var(--premium-radius);
}

.site-footer {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-nav a {
  color: rgba(238, 242, 251, 0.62);
}

.footer-nav a:hover {
  color: var(--accent-strong);
}

.simulator-top-back,
.simulation-back-floating {
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.32), 0 0 0 1px rgba(82, 214, 230, 0.14);
}

.math-keyboard {
  max-width: 100%;
  overflow: hidden;
  padding: 14px;
  border-color: rgba(82, 214, 230, 0.14);
  background:
    linear-gradient(180deg, rgba(15, 23, 42, 0.74), rgba(7, 11, 22, 0.66)),
    rgba(7, 11, 22, 0.72);
}

.math-keyboard-head {
  gap: 10px;
  margin-bottom: 10px;
}

.math-keyboard-head span,
.math-keyboard-head strong {
  min-width: 0;
}

.symbolic-state {
  margin-bottom: 12px;
  padding: 10px 12px;
  overflow-x: auto;
  overflow-y: hidden;
  font-size: 0.88rem;
  line-height: 1.35;
  white-space: nowrap;
}

.math-key-grid {
  width: fit-content;
  max-width: 100%;
  grid-template-columns: repeat(9, minmax(48px, 64px));
  justify-content: start;
  gap: 7px;
}

.math-key-grid button,
.math-state-presets button {
  min-width: 0;
  min-height: 38px;
  padding: 8px 9px;
  border-radius: 8px;
  line-height: 1.05;
  white-space: nowrap;
}

.math-key-grid button {
  overflow: hidden;
  justify-content: center;
  font-family: "Cambria Math", Cambria, Georgia, serif;
  font-size: 13px;
  text-overflow: ellipsis;
}

.math-key-grid .math-command {
  grid-column: span 2;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.06em;
}

.math-key-grid button:nth-child(21) {
  font-size: 12px;
}

.math-state-presets {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(54px, max-content));
  align-items: center;
  justify-content: start;
  gap: 7px;
  margin-top: 12px;
  padding-top: 12px;
}

.math-state-presets > span {
  grid-column: 1 / -1;
  margin-bottom: 0;
}

.activity-card {
  width: min(100%, 824px);
  justify-self: center;
  gap: 12px;
  padding: 24px;
}

.activity-card .mini-formula,
.activity-card .answer-grid,
.activity-card .activity-feedback {
  width: 100%;
  max-width: none;
}

.activity-card .mini-formula {
  margin: 0;
  padding: 14px 16px;
  border-color: rgba(82, 214, 230, 0.18);
  border-radius: 8px;
  background: rgba(7, 11, 22, 0.46);
  font-size: clamp(1rem, 1.4vw, 1.12rem);
  line-height: 1.35;
  white-space: nowrap;
  overflow-x: auto;
}

.activity-card h4 {
  max-width: none;
  margin: 0;
  color: var(--text-main);
  font-family: var(--font);
  font-size: clamp(1rem, 1.45vw, 1.18rem);
  font-weight: 700;
  line-height: 1.35;
  letter-spacing: 0;
}

.activity-card .answer-grid {
  grid-template-columns: repeat(auto-fit, minmax(min(210px, 100%), 1fr));
  gap: 10px;
}

.activity-card .answer-grid button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 12px;
  border-radius: 8px;
  font-family: var(--mono);
  font-size: 0.9rem;
  font-weight: 700;
  line-height: 1.22;
  text-align: center;
  white-space: normal;
  overflow-wrap: anywhere;
  text-wrap: balance;
}

.activity-card .activity-feedback {
  min-height: 46px;
  margin: 0;
  padding: 12px 14px;
  border-color: rgba(154, 166, 198, 0.16);
  border-radius: 8px;
  background: rgba(15, 23, 42, 0.58);
  color: var(--text-muted);
  line-height: 1.45;
}

main .activity-card p.mini-formula:not(.eyebrow):not(.section-kicker):not(.formula-caption),
main .activity-card p.activity-feedback:not(.eyebrow):not(.section-kicker):not(.formula-caption) {
  width: 100%;
  max-width: none;
}

.simulator-accordion-body[hidden],
.simulator-inline-accordion-body[hidden],
.concept-content[hidden] {
  display: none !important;
}

@media (max-width: 720px) {
  p,
  li {
    line-height: 1.68;
  }

  .feature-card,
  .concept-card,
  .comparison-card,
  .activity-card,
  .instrument-card,
  .simulation-card,
  .lab-panel,
  .topic-card {
    padding: 20px;
  }

  .math-key-grid {
    width: 100%;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 6px;
  }

  .math-key-grid button,
  .math-state-presets button {
    min-height: 36px;
    padding: 7px 6px;
  }

  .math-key-grid .math-command {
    font-size: 9px;
  }

  .math-key-grid button:nth-child(21) {
    font-size: 10px;
  }

  .symbolic-state {
    font-size: 0.82rem;
  }

  .math-state-presets {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .activity-card {
    width: 100%;
    gap: 12px;
  }

  .activity-card .mini-formula {
    padding: 12px 13px;
    font-size: 0.95rem;
  }

  .activity-card .answer-grid {
    grid-template-columns: 1fr;
  }

  .activity-card .answer-grid button {
    min-height: 42px;
  }

  .development-toast {
    bottom: 18px;
    border-radius: 18px;
    font-size: 12px;
  }

  .contact-actions {
    display: grid;
  }
}

/* Mobile simulator repair: keep all controls reachable without changing simulator logic. */
@media (max-width: 768px) {
  .simulator-body {
    overflow-x: hidden;
  }

  .simulator-body main,
  .simulator-body .page-shell,
  .simulator-body .simulator-lab,
  .simulator-body .simulator-flow,
  .simulator-body .simulator-section,
  .simulator-body .simulator-main-grid,
  .simulator-body .state-definition-grid,
  .simulator-body .simulator-visual-grid,
  .simulator-body .simulator-results-grid,
  .simulator-body .simulator-support-grid,
  .simulator-body .simulator-decoherence-grid,
  .simulator-body .simulator-learning-grid,
  .simulator-body .simulator-export-grid,
  .quantum-sim-layout,
  .quantum-sim-grid,
  .panel-grid {
    width: 100%;
    max-width: 100%;
    min-width: 0;
    grid-template-columns: 1fr !important;
  }

  .simulator-body .simulator-flow {
    display: flex;
    flex-direction: column;
    gap: 44px;
  }

  .simulator-body .simulator-hero {
    min-height: auto;
    padding-top: 104px;
    padding-bottom: 42px;
  }

  .simulator-body .simulator-lab {
    padding-top: 36px;
    padding-bottom: 64px;
  }

  .simulator-body .page-shell,
  .simulator-body .site-shell {
    width: min(100% - 36px, 1200px);
    margin-right: auto;
    margin-left: auto;
  }

  .simulator-body .simulator-intro,
  .simulator-body .simulator-intro > p,
  .simulator-body .simulator-intro h1 {
    max-width: 100%;
    overflow-wrap: anywhere;
  }

  .simulator-body .simulator-intro h1 {
    font-size: clamp(2rem, 7.8vw, 2.85rem);
    line-height: 1.06;
  }

  .simulator-body .simulator-intro > p {
    margin-top: 0.9rem;
    font-size: 1rem;
    line-height: 1.58;
  }

  .simulator-body .simulator-guide {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
    margin-top: 1rem;
  }

  .simulator-body .simulator-guide span {
    min-height: 42px;
    padding: 10px;
    font-size: 0.78rem;
    line-height: 1.3;
  }

  .simulator-body .hero-metrics,
  .simulator-body .simulator-help-actions {
    display: none;
  }

  .simulator-body .mode-switch {
    display: grid;
    grid-auto-flow: column;
    grid-template-columns: auto minmax(0, 1fr) minmax(0, 1fr);
    width: 100%;
    margin-top: 1rem;
  }

  .simulator-body .simulator-flow > .simulator-section:nth-of-type(1) {
    order: 2;
  }

  .simulator-body .simulator-flow > .simulator-section:nth-of-type(2) {
    order: 1;
  }

  .simulator-body .simulator-flow > .simulator-section:nth-of-type(3) {
    order: 4;
  }

  .simulator-body .simulator-flow > .simulator-section:nth-of-type(4) {
    order: 3;
  }

  .simulator-body .simulator-flow > .simulator-section:nth-of-type(5) {
    order: 5;
  }

  .simulator-body .simulator-flow > .simulator-section:nth-of-type(6) {
    order: 6;
  }

  .simulator-body .simulator-section + .simulator-section {
    margin-top: 0;
  }

  .simulator-body .simulator-section-header {
    grid-template-columns: 1fr;
    gap: 12px;
    margin-bottom: 18px;
  }

  .simulator-body .simulator-section-index {
    width: 38px;
  }

  .simulator-body .lab-panel,
  .simulator-body .controls-panel,
  .simulator-body .ket-panel,
  .simulator-body .decoherence-controls-panel,
  .simulator-body .probability-panel,
  .simulator-body .matrix-panel,
  .simulator-body .coherence-panel,
  .simulator-body .purity-panel,
  .simulator-body .compare-panel,
  .simulator-body .measurement-panel,
  .simulator-body .development-panel,
  .simulator-body .report-panel,
  .simulator-body .glossary-panel {
    display: block;
    visibility: visible;
    opacity: 1;
    position: relative;
    transform: none;
    width: 100%;
    max-width: 100%;
    min-width: 0;
    height: auto;
    max-height: none;
    z-index: 1;
    overflow: visible;
  }

  .simulator-body .bloch-panel,
  .simulator-body .chart-panel,
  .simulator-body .simulation-stage-card {
    width: 100%;
    max-width: 100%;
    min-width: 0;
    overflow: hidden;
  }

  .simulator-body .simulator-state-stack,
  .simulator-body .custom-controls,
  .simulator-body .control-cluster,
  .simulator-body .state-actions,
  .simulator-body .development-actions,
  .simulator-body .compact-actions,
  .simulator-body .compare-grid,
  .simulator-body .readout-row,
  .simulator-body .readout-grid,
  .simulator-body .measurement-actions,
  .simulator-body .report-summary-grid,
  .simulator-body .button-grid,
  .simulator-body .preset-buttons,
  .simulator-body .math-state-presets,
  .quantum-sim-grid .control-cluster,
  .quantum-sim-grid .button-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    width: 100%;
    max-width: 100%;
    min-width: 0;
  }

  .simulator-body .preset-buttons,
  .simulator-body .math-state-presets {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .simulator-body .control-group {
    display: grid;
    grid-template-columns: 1fr;
    gap: 10px;
    width: 100%;
    max-width: 100%;
    min-width: 0;
    overflow: visible;
  }

  .simulator-body input,
  .simulator-body select,
  .simulator-body textarea,
  .quantum-sim-grid input,
  .quantum-sim-grid select,
  .quantum-sim-grid textarea {
    width: 100%;
    max-width: 100%;
    min-width: 0;
    min-height: 44px;
  }

  .simulator-body input[type="range"],
  .quantum-sim-grid input[type="range"] {
    min-height: 32px;
  }

  .simulator-body .mini-button,
  .simulator-body .preset-button,
  .simulator-body .quantum-button,
  .simulator-body .option-button,
  .simulator-body .sim-button,
  .simulator-body .math-key-grid button,
  .simulator-body .math-state-presets button,
  .quantum-sim-grid button {
    width: 100%;
    min-width: 0;
    min-height: 42px;
    white-space: normal;
    overflow-wrap: anywhere;
  }

  .simulator-body .math-keyboard,
  .simulator-body .simulator-inline-accordion,
  .simulator-body .simulator-inline-accordion-body {
    width: 100%;
    max-width: 100%;
    min-width: 0;
    overflow: visible;
  }

  .simulator-body .math-key-grid {
    display: grid;
    width: 100%;
    max-width: 100%;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 7px;
  }

  .simulator-body .math-key-grid .math-command {
    grid-column: span 2;
  }

  .simulator-body .symbolic-state,
  .simulator-body .ket-display,
  .simulator-body .formula-box,
  .simulator-body .mini-formula,
  .simulator-body .formula-stack code,
  .simulator-body .code-sample,
  .simulator-body .matrix,
  .simulator-body .mini-matrix,
  .simulator-body .density-matrix,
  .simulator-body .density-matrix-figure,
  .simulator-body .visual-matrix,
  .simulator-body .matrix-table,
  .simulator-body .results-table,
  .panel-grid pre,
  .quantum-sim-grid pre {
    max-width: 100%;
    min-width: 0;
    overflow-x: auto;
    overflow-y: hidden;
  }

  .simulator-body .matrix,
  .simulator-body .mini-matrix {
    width: 100%;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
    padding: 12px;
  }

  .simulator-body .matrix span,
  .simulator-body .mini-matrix span {
    min-width: 0;
    min-height: 60px;
    padding: 8px;
    overflow-wrap: anywhere;
    font-size: clamp(0.9rem, 4vw, 1.08rem);
  }

  .simulator-body .bloch-stage,
  .simulator-body .bloch-stage-3d,
  .simulator-body .bloch-viewer,
  .simulator-body .bloch-card {
    width: 100%;
    max-width: 100%;
    min-height: 300px;
  }

  .simulator-body .bloch-stage canvas,
  .simulator-body .bloch-viewer canvas,
  .simulator-body #bloch3d canvas,
  .simulator-body canvas[data-bloch-canvas] {
    display: block;
    width: 100% !important;
    max-width: 100%;
    height: 300px !important;
  }

  .simulator-body .chart-wrap {
    min-height: 240px;
    padding: 0.6rem 0.25rem 1.45rem 0.9rem;
  }

  .simulator-body .chart-wrap canvas,
  .quantum-sim-grid canvas,
  .panel-grid canvas,
  .experiment-canvas {
    display: block;
    width: 100% !important;
    max-width: 100%;
    height: auto;
  }

  .simulator-body .chart-wrap canvas {
    height: 220px !important;
  }

  .simulator-top-back {
    left: max(8px, env(safe-area-inset-left));
    max-width: calc(100vw - 24px);
  }

  .simulation-back-floating {
    display: none;
  }
}

@media (max-width: 430px) {
  .simulator-body .page-shell,
  .simulator-body .site-shell {
    width: min(100% - 28px, 1200px);
    margin-right: auto;
    margin-left: auto;
  }

  .simulator-body .simulator-hero {
    padding-top: 112px;
    padding-bottom: 54px;
  }

  .simulator-body h1,
  .simulator-body .simulator-intro h1 {
    font-size: clamp(1.95rem, 7.6vw, 2.35rem);
    line-height: 1.08;
  }

  .simulator-body h2,
  .simulator-body .simulator-section-header h2 {
    font-size: clamp(1.55rem, 8vw, 2.2rem);
  }

  .simulator-body .feature-card,
  .simulator-body .concept-card,
  .simulator-body .comparison-card,
  .simulator-body .activity-card,
  .simulator-body .instrument-card,
  .simulator-body .simulation-card,
  .simulator-body .lab-panel,
  .simulator-body .topic-card {
    padding: 18px;
  }

  .simulator-body .math-key-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .simulator-body .math-state-presets {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .simulator-body .bloch-stage,
  .simulator-body .bloch-stage-3d {
    min-height: 280px;
  }

  .simulator-body .bloch-stage canvas,
  .simulator-body canvas[data-bloch-canvas] {
    height: 280px !important;
  }

  .simulator-body .simulation-back-floating {
    display: none;
  }
}

/* Video lessons library */
.video-lessons-hero .page-hero-inner {
  max-width: 920px;
}

.video-lessons-hero {
  min-height: 390px;
  padding: 126px 0 54px;
}

.video-lessons-hero .page-hero-inner {
  min-height: 210px;
}

.video-lessons-hero .page-hero-inner > p:last-child {
  max-width: 880px;
  margin-top: 18px;
}

.video-library-section {
  padding-top: clamp(58px, 7vw, 90px);
}

.video-track-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(280px, 0.55fr);
  gap: clamp(26px, 5vw, 68px);
  align-items: end;
}

.video-track-heading h2 {
  max-width: 780px;
  font-size: clamp(2rem, 4.2vw, 3.85rem);
}

.video-track-heading > p {
  max-width: 520px;
  padding-bottom: 7px;
}

.video-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-top: clamp(28px, 4vw, 48px);
}

.video-filter {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 9px 14px;
  border: 1px solid var(--line);
  border-radius: 0;
  color: var(--muted-strong);
  background: rgba(13, 20, 38, 0.56);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.055em;
  text-transform: uppercase;
  cursor: pointer;
  transition:
    color 240ms ease,
    border-color 240ms ease,
    background 240ms ease,
    transform 240ms ease;
}

.video-filter:hover {
  border-color: rgba(82, 214, 230, 0.42);
  color: var(--text);
  transform: translateY(-2px);
}

.video-filter.is-active {
  border-color: var(--cyan);
  color: #04222a;
  background: var(--cyan);
}

.video-results-status {
  margin-top: 16px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
}

.video-lessons-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(18px, 2vw, 26px);
  margin-top: 28px;
}

.video-card {
  position: relative;
  display: flex;
  min-width: 0;
  min-height: 390px;
  flex-direction: column;
  gap: 18px;
  overflow: hidden;
  padding: clamp(22px, 2.4vw, 28px);
  border: 1px solid var(--line);
  background:
    linear-gradient(145deg, rgba(82, 214, 230, 0.035), transparent 46%),
    var(--surface);
  transition:
    transform 380ms var(--motion-ease),
    border-color 380ms ease,
    background 380ms ease;
}

.video-card::before {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 2px;
  content: "";
  background: var(--cyan);
  transition: width 420ms var(--motion-ease);
}

.video-card:hover {
  border-color: rgba(82, 214, 230, 0.36);
  background:
    linear-gradient(145deg, rgba(82, 214, 230, 0.065), transparent 48%),
    var(--surface);
  transform: translateY(-4px);
}

.video-card:hover::before {
  width: 100%;
}

.video-card[hidden] {
  display: none;
}

.video-card-featured {
  border-color: rgba(82, 214, 230, 0.28);
}

.video-card-topline {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
  align-items: center;
  justify-content: space-between;
}

.video-status,
.video-card-index,
.video-duration,
.video-duration span {
  font-family: var(--mono);
}

.video-status {
  width: fit-content;
  padding: 5px 9px;
  border-radius: 999px;
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.video-status.preparation {
  border: 1px solid rgba(237, 178, 78, 0.38);
  color: #f5c66f;
  background: rgba(237, 178, 78, 0.09);
}

.video-status.published {
  border: 1px solid rgba(82, 214, 230, 0.36);
  color: var(--cyan);
  background: rgba(82, 214, 230, 0.09);
}

.video-card-index {
  margin: 0;
  color: var(--cyan);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.video-card-content {
  display: grid;
  gap: 12px;
}

.video-card h3 {
  font-family: var(--serif);
  font-size: clamp(1.45rem, 2vw, 1.85rem);
  font-weight: 400;
  overflow-wrap: anywhere;
}

.video-description {
  font-size: 0.94rem;
  line-height: 1.65;
}

.video-duration {
  display: flex;
  gap: 12px;
  align-items: center;
  margin-top: auto;
  padding: 11px 12px;
  border: 1px solid rgba(154, 166, 198, 0.14);
  color: var(--text);
  background: rgba(7, 11, 22, 0.44);
  font-size: 0.82rem;
}

.video-duration span {
  color: var(--muted);
  font-size: 9px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.video-card-action {
  width: 100%;
  min-height: 46px;
  cursor: pointer;
}

.video-modal {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: grid;
  place-items: center;
  overflow-y: auto;
  padding: 24px;
}

.video-modal[hidden] {
  display: none;
}

.video-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(3, 7, 18, 0.82);
  backdrop-filter: blur(14px);
  cursor: pointer;
}

.video-modal-content {
  position: relative;
  z-index: 1;
  width: min(960px, 100%);
  max-height: calc(100dvh - 48px);
  overflow-y: auto;
  padding: clamp(14px, 2vw, 22px);
  border: 1px solid rgba(82, 214, 230, 0.28);
  border-radius: 22px;
  outline: none;
  background: rgba(7, 11, 22, 0.96);
  box-shadow: 0 28px 90px rgba(0, 0, 0, 0.48);
}

.video-modal-content:focus-visible {
  border-color: rgba(82, 214, 230, 0.58);
}

.video-modal-header {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 16px;
}

.video-modal-eyebrow {
  margin-bottom: 6px;
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.video-modal-header h2 {
  max-width: 720px;
  font-size: clamp(1.35rem, 3vw, 2rem);
}

.video-modal-close {
  flex: 0 0 auto;
  padding: 8px 12px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 999px;
  color: var(--text);
  background: rgba(7, 11, 22, 0.82);
  cursor: pointer;
  transition:
    color 220ms ease,
    border-color 220ms ease;
}

.video-modal-close:hover,
.video-modal-close:focus-visible {
  border-color: rgba(82, 214, 230, 0.55);
  color: var(--cyan);
}

.video-player {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: 16px;
  background: #000;
}

body.video-modal-open {
  overflow: hidden;
}

.video-empty-state {
  margin-top: 28px;
  padding: clamp(28px, 5vw, 54px);
  border: 1px dashed rgba(82, 214, 230, 0.3);
  text-align: center;
  background: rgba(13, 20, 38, 0.5);
}

.video-empty-state[hidden] {
  display: none;
}

.video-empty-state h3 {
  margin-top: 9px;
  font-size: clamp(1.7rem, 3vw, 2.3rem);
}

.video-empty-state > p:not(.section-kicker) {
  max-width: 620px;
  margin: 14px auto 0;
}

.video-empty-state .button {
  margin-top: 24px;
}

.video-library-note {
  max-width: 760px;
  margin: 34px auto 0;
  color: var(--muted);
  font-size: 0.82rem;
  text-align: center;
}

.video-embed {
  position: relative;
  width: 100%;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 18px;
  background: rgba(7, 11, 22, 0.72);
}

.video-embed iframe {
  width: 100%;
  height: 100%;
  border: 0;
}

.video-toast {
  position: fixed;
  right: max(20px, env(safe-area-inset-right));
  bottom: max(20px, env(safe-area-inset-bottom));
  z-index: 80;
  width: min(420px, calc(100vw - 40px));
  padding: 16px 18px;
  border: 1px solid rgba(237, 178, 78, 0.4);
  color: var(--text);
  background: rgba(7, 11, 22, 0.96);
  box-shadow: 0 22px 70px rgba(0, 0, 0, 0.46);
  font-size: 0.9rem;
  line-height: 1.55;
  opacity: 0;
  pointer-events: none;
  transform: translateY(14px);
  transition:
    opacity 240ms ease,
    transform 320ms var(--motion-ease);
}

.video-toast.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (min-width: 981px) and (max-width: 1210px) {
  .main-nav {
    gap: 0.12rem;
  }

  .main-nav a {
    padding-inline: 0.5rem;
    font-size: 0.84rem;
  }
}

@media (max-width: 980px) {
  .video-track-heading {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .video-lessons-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .video-lessons-page .page-shell {
    width: min(100% - 30px, 1160px);
  }

  .video-lessons-page .page-hero {
    min-height: 360px;
    padding-top: 112px;
    padding-bottom: 42px;
  }

  .video-lessons-hero .page-hero-inner {
    min-height: 190px;
  }

  .video-filters {
    gap: 8px;
  }

  .video-filter {
    min-height: 44px;
    padding-inline: 12px;
    font-size: 10px;
  }

  .video-lessons-grid {
    grid-template-columns: 1fr;
  }

  .video-card {
    min-height: 0;
  }

  .video-modal {
    padding: 14px;
  }

  .video-modal-content {
    max-height: calc(100dvh - 28px);
    padding: 12px;
    border-radius: 18px;
  }

  .video-modal-header {
    display: grid;
    gap: 12px;
  }

  .video-modal-close {
    justify-self: start;
  }

  .video-player {
    border-radius: 12px;
  }

  .video-toast {
    right: 15px;
    bottom: max(15px, env(safe-area-inset-bottom));
    width: calc(100vw - 30px);
  }
}

@media (max-width: 430px) {
  .video-filter {
    flex: 1 1 calc(50% - 8px);
    justify-content: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal,
  .reveal.in-view {
    opacity: 1 !important;
    transform: none !important;
  }

  body.is-ready main,
  body.page-leaving main,
  body::before,
  body::after,
  .simulator-top-back,
  .simulation-back-floating,
  .simulation-stage-card::after {
    animation: none !important;
    transform: none !important;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}