:root {
  --bg-0: #08080f;
  --bg-1: #12091f;
  --bg-2: #201039;
  --text: #f8f7ff;
  --text-dim: #c7c3db;
  --panel: rgba(13, 10, 22, 0.84);
  --panel-border: rgba(167, 139, 250, 0.35);
  --accent: #a78bfa;
  --accent-soft: rgba(167, 139, 250, 0.2);
  --code-bg: rgba(6, 5, 12, 0.82);
  --code-line: rgba(147, 133, 255, 0.04);
  --code-active: rgba(167, 139, 250, 0.18);
  --code-active-glow: rgba(167, 139, 250, 0.5);
  --code-search: rgba(99, 179, 237, 0.25);
  --shadow: 0 18px 60px rgba(0, 0, 0, 0.35);
}

* {
  box-sizing: border-box;
}

html,
body,
#root {
  width: 100%;
  min-height: 100%;
  margin: 0;
}

body {
  font-family: Inter, "Segoe UI", Roboto, Arial, sans-serif;
  color: var(--text);
  background:
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    radial-gradient(1400px 900px at 15% 0%, #2e1553 0%, transparent 45%),
    linear-gradient(140deg, var(--bg-0), var(--bg-1) 45%, var(--bg-2));
  background-size:
    40px 40px,
    40px 40px,
    auto,
    auto;
}

.app-shell {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2.75rem 1.25rem 3rem;
}

.topbar h1 {
  margin: 0.4rem 0 0.35rem;
  font-size: clamp(2rem, 5vw, 3rem);
  line-height: 1.08;
}

.badge {
  display: inline-block;
  margin: 0;
  padding: 0.25rem 0.6rem;
  border: 1px solid var(--panel-border);
  border-radius: 999px;
  color: #ddd5ff;
  letter-spacing: 0.06em;
  font-size: 0.75rem;
  text-transform: uppercase;
  background: rgba(167, 139, 250, 0.12);
}

.subtitle {
  margin: 0;
  color: var(--text-dim);
}

.content {
  margin-top: 1.6rem;
}

.panel {
  padding: 1rem 1.1rem;
  border: 1px solid var(--panel-border);
  border-radius: 14px;
  background: var(--panel);
  backdrop-filter: blur(6px);
  box-shadow: var(--shadow);
}

.panel h2 {
  margin: 0 0 0.75rem;
}

.panel p,
.panel li {
  color: var(--text-dim);
}

.panel ul {
  margin: 0.75rem 0 0;
  padding-left: 1.1rem;
}

a {
  color: #ddd5ff;
}

.home-links li {
  margin-bottom: 0.4rem;
}

.home-stack {
  display: grid;
  gap: 0.9rem;
}

.lab-tabs {
  display: flex;
  gap: 0.6rem;
  margin-top: 0.8rem;
}

.tab-btn {
  border: 1px solid var(--panel-border);
  background: transparent;
  color: var(--text);
  padding: 0.45rem 0.8rem;
  border-radius: 10px;
  cursor: pointer;
  transition: 140ms ease all;
}

.tab-btn:hover {
  background: var(--accent-soft);
}

.tab-btn.active {
  background: rgba(167, 139, 250, 0.28);
  box-shadow: 0 0 0 1px rgba(167, 139, 250, 0.3) inset;
}

.two-pane {
  display: grid;
  grid-template-columns: minmax(240px, 0.9fr) minmax(420px, 1.4fr);
  gap: 0.9rem;
}

.subpanel {
  background: rgba(10, 8, 19, 0.72);
}

.small-btn {
  border: 1px solid var(--panel-border);
  color: var(--text);
  background: rgba(167, 139, 250, 0.12);
  border-radius: 8px;
  padding: 0.35rem 0.6rem;
  cursor: pointer;
  transition: 140ms ease background, 140ms ease border-color, 140ms ease transform, 140ms ease box-shadow;
}

.small-btn:hover {
  background: rgba(167, 139, 250, 0.22);
}

.small-btn:focus-visible,
.tab-btn:focus-visible,
.chip:focus-visible,
.lab-tile:focus-visible {
  outline: none;
  box-shadow: 0 0 0 2px rgba(167, 139, 250, 0.32), 0 0 24px rgba(167, 139, 250, 0.14);
}

.player-controls {
  display: flex;
  gap: 0.5rem;
  margin: 0.55rem 0;
}

.scene-wrap {
  border: 1px solid rgba(167, 139, 250, 0.3);
  border-radius: 10px;
  overflow: hidden;
  background: radial-gradient(1000px 500px at 10% 0%, rgba(111, 76, 183, 0.24), rgba(8, 7, 14, 0.9));
}

.scene-svg {
  width: 100%;
  height: auto;
  display: block;
}

.scene-node {
  stroke: #cdbdff;
  fill: none;
}

.scene-node.muted {
  stroke: rgba(205, 189, 255, 0.5);
}

.scene-node.dashed {
  stroke-dasharray: 6 5;
}

.scene-node.text {
  fill: #efe7ff;
  stroke: none;
  font-size: 13px;
  font-weight: 500;
}

.scene-arrow-head {
  fill: #cdbdff;
}

.po-visual-stack {
  display: grid;
  gap: 0.7rem;
}

.po-recovery {
  border: 1px solid rgba(167, 139, 250, 0.24);
  background: rgba(9, 8, 17, 0.78);
  border-radius: 10px;
  padding: 0.6rem 0.8rem;
}

.po-mono {
  font-family: Consolas, "Courier New", monospace;
  margin: 0.2rem 0;
  color: #f0e7ff;
}

.po-hex {
  color: #c7ffea;
  font-size: 0.82rem;
}

.po-chart {
  border: 1px solid rgba(167, 139, 250, 0.24);
  border-radius: 10px;
  padding: 0.5rem 0.6rem;
  background: rgba(9, 8, 17, 0.72);
}

.tc-visual-grid {
  display: grid;
  gap: 0.75rem;
}

.tc-panel {
  border: 1px solid rgba(167, 139, 250, 0.24);
  border-radius: 12px;
  padding: 0.6rem 0.75rem;
  background: rgba(9, 8, 17, 0.72);
}

.tc-timeline {
  display: grid;
  gap: 0.55rem;
}

.tc-strip {
  display: grid;
  gap: 0.2rem;
}

.tc-strip-label {
  color: rgba(248, 247, 255, 0.85);
  font-size: 0.82rem;
}

.tc-bar {
  fill: rgba(167, 139, 250, 0.75);
}

.tc-scores {
  display: grid;
  gap: 0.4rem;
  margin-top: 0.35rem;
}

.tc-score-row {
  display: grid;
  grid-template-columns: 64px 1fr 72px;
  align-items: center;
  gap: 0.55rem;
}

.tc-score-label {
  font-family: Consolas, "Courier New", monospace;
  color: rgba(199, 195, 219, 0.95);
}

.tc-score-bar {
  height: 10px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(167, 139, 250, 0.18);
  overflow: hidden;
}

.tc-score-fill {
  height: 100%;
  background: linear-gradient(90deg, rgba(167, 139, 250, 0.9), rgba(99, 179, 237, 0.65));
}

.tc-score-val {
  text-align: right;
  font-family: Consolas, "Courier New", monospace;
  color: rgba(248, 247, 255, 0.9);
}

.tc-point {
  fill: rgba(167, 139, 250, 0.9);
  stroke: rgba(255, 255, 255, 0.15);
  stroke-width: 1.2;
}

.tc-toggles {
  display: flex;
  gap: 0.85rem;
  margin: 0.6rem 0 0.8rem;
}

.tc-toggle {
  display: inline-flex;
  gap: 0.4rem;
  align-items: center;
  color: rgba(248, 247, 255, 0.86);
  font-size: 0.9rem;
}

.tc-toggle input {
  accent-color: rgba(167, 139, 250, 0.95);
}

.li-visual-grid {
  display: grid;
  gap: 0.75rem;
}

.li-panel {
  border: 1px solid rgba(167, 139, 250, 0.24);
  border-radius: 12px;
  padding: 0.6rem 0.75rem;
  background: rgba(9, 8, 17, 0.72);
}

.li-hist-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.7rem;
}

.li-hist-title {
  color: rgba(248, 247, 255, 0.86);
  font-size: 0.85rem;
  margin-bottom: 0.15rem;
}

.li-bar {
  opacity: 0.95;
}

.li-bar.li0 {
  fill: rgba(99, 179, 237, 0.72);
}

.li-bar.li1 {
  fill: rgba(167, 139, 250, 0.72);
}

.li-meter {
  height: 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(167, 139, 250, 0.18);
  overflow: hidden;
  margin-top: 0.4rem;
}

.li-meter-fill {
  height: 100%;
  background: linear-gradient(90deg, rgba(99, 179, 237, 0.75), rgba(167, 139, 250, 0.85));
}

.li-meter-label {
  font-family: Consolas, "Courier New", monospace;
  font-size: 0.9rem;
  color: rgba(248, 247, 255, 0.86);
}

.li-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 0.5rem;
  margin: 0.45rem 0 0.2rem;
}

@media (max-width: 900px) {
  .li-hist-grid,
  .li-grid {
    grid-template-columns: 1fr;
  }
}

.field-label {
  display: block;
  font-size: 0.78rem;
  color: var(--text-dim);
  margin-bottom: 0.2rem;
}

.code-layout {
  display: grid;
  gap: 0.8rem;
}

.code-top {
  display: grid;
  grid-template-columns: minmax(230px, 0.8fr) minmax(420px, 1.5fr);
  gap: 0.8rem;
}

.step-list ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.step-item button {
  width: 100%;
  text-align: left;
  border: 1px solid rgba(167, 139, 250, 0.2);
  background: rgba(167, 139, 250, 0.08);
  border-radius: 8px;
  padding: 0.48rem 0.55rem;
  color: var(--text);
  cursor: pointer;
}

.step-item.active button {
  border-color: var(--accent);
  background: rgba(167, 139, 250, 0.3);
}

.step-title {
  display: block;
  font-size: 0.92rem;
}

.step-id {
  display: block;
  margin-top: 0.25rem;
  color: var(--text-dim);
  font-size: 0.78rem;
}

.explanation-pane p {
  margin: 0.35rem 0;
}

.code-viewer {
  display: grid;
  gap: 0.65rem;
}

.code-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  align-items: center;
}

.code-file {
  font-size: 0.85rem;
  color: #e9dcff;
  padding: 0.1rem 0.4rem;
  border-radius: 999px;
  background: rgba(167, 139, 250, 0.15);
}

.code-search {
  min-width: 180px;
  border-radius: 8px;
  border: 1px solid rgba(167, 139, 250, 0.3);
  background: rgba(13, 11, 22, 0.8);
  color: var(--text);
  padding: 0.38rem 0.52rem;
}

.code-scroll {
  max-height: 480px;
  overflow: auto;
  border: 1px solid rgba(167, 139, 250, 0.24);
  border-radius: 10px;
  background: var(--code-bg);
}

.code-line {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 0.65rem;
  font-family: Consolas, "Courier New", monospace;
  font-size: 0.86rem;
  line-height: 1.45;
  border-bottom: 1px solid rgba(255, 255, 255, 0.03);
  background: var(--code-line);
}

.line-no {
  text-align: right;
  color: rgba(199, 195, 219, 0.8);
  padding: 0.22rem 0.4rem 0.22rem 0;
  user-select: none;
  border-right: 1px solid rgba(167, 139, 250, 0.15);
}

.line-code {
  white-space: pre;
  padding: 0.22rem 0.5rem 0.22rem 0;
  color: #f3edff;
}

.code-line.active {
  background: var(--code-active);
  box-shadow: inset 2px 0 0 var(--accent), 0 0 22px -8px var(--code-active-glow);
}

.code-line.search-hit:not(.active) {
  background: var(--code-search);
}

.copy-msg {
  color: #d7f5de;
  font-size: 0.9rem;
}

.error {
  margin-top: 0.8rem;
  border-color: rgba(255, 120, 120, 0.5);
}

@media (max-width: 900px) {
  .two-pane,
  .code-top {
    grid-template-columns: 1fr;
  }
}

.story-player {
  display: grid;
  gap: 0.75rem;
}

.story-top {
  padding: 0.9rem;
}

.story-bottom {
  padding: 0.9rem 1rem;
}

.story-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  margin-bottom: 0.6rem;
}

.story-spacer {
  flex: 1;
}

.story-duration {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  color: var(--text-dim);
  font-size: 0.85rem;
}

.story-duration input {
  width: 4.2rem;
  border-radius: 8px;
  border: 1px solid rgba(167, 139, 250, 0.3);
  background: rgba(13, 11, 22, 0.8);
  color: var(--text);
  padding: 0.32rem 0.45rem;
}

.story-meta {
  display: flex;
  gap: 0.65rem;
  align-items: baseline;
}

.story-step {
  color: #e9dcff;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  border: 1px solid rgba(167, 139, 250, 0.3);
  background: rgba(167, 139, 250, 0.12);
  font-size: 0.82rem;
}

.story-title {
  font-size: 0.98rem;
  color: var(--text);
}

.story-explain {
  margin: 0.55rem 0 0;
  color: var(--text-dim);
  line-height: 1.55;
  font-size: 0.95rem;
}

.overlay-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(3px);
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 1.25rem;
}

.code-overlay {
  width: min(980px, 96vw);
  max-height: min(88vh, 860px);
  overflow: auto;
  border-radius: 14px;
  border: 1px solid rgba(167, 139, 250, 0.4);
  background: rgba(10, 8, 18, 0.92);
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.45);
  padding: 0.9rem;
}

.code-overlay-header {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.65rem;
}

.code-overlay-header h4 {
  margin: 0;
  color: #efe8ff;
}

.code-map-item {
  list-style: none;
  margin-bottom: 0.8rem;
}

.code-map-row {
  display: flex;
  gap: 0.65rem;
  align-items: center;
  justify-content: space-between;
}

.code-map-id {
  color: #efe8ff;
  font-size: 0.92rem;
}

.code-map-desc {
  margin-top: 0.25rem;
  color: var(--text-dim);
  font-size: 0.9rem;
  line-height: 1.4;
}

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 0.7rem;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.18rem 0.55rem;
  border-radius: 999px;
  border: 1px solid rgba(167, 139, 250, 0.28);
  background: rgba(167, 139, 250, 0.1);
  color: #efe8ff;
  font-size: 0.78rem;
  letter-spacing: 0.02em;
}

.hero {
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: -120px -120px auto -120px;
  height: 320px;
  background: radial-gradient(circle at 20% 20%, rgba(167, 139, 250, 0.25), transparent 60%);
  pointer-events: none;
}

.hero-title {
  margin: 0.65rem 0 0.5rem;
  font-size: clamp(1.6rem, 3.8vw, 2.35rem);
  line-height: 1.15;
}

.hero-top {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 1.1rem;
  align-items: start;
  position: relative;
  z-index: 1;
}

.hero-controls {
  margin-top: 0.75rem;
}

.hero-diagram .scene-wrap {
  border-radius: 14px;
  border: 1px solid rgba(167, 139, 250, 0.18);
  background: rgba(6, 5, 12, 0.35);
}

.hero-demo {
  display: grid;
  grid-template-columns: 1.25fr 0.75fr;
  gap: 0.9rem;
  margin-top: 1rem;
  position: relative;
  z-index: 1;
}

.hero-story h4 {
  margin: 0;
  color: #efe8ff;
}

.hero-hint {
  margin: 0.65rem 0 0;
  font-size: 0.9rem;
  color: rgba(199, 195, 219, 0.92);
}

.step-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 0.65rem;
}

.chip {
  border-radius: 999px;
  border: 1px solid rgba(167, 139, 250, 0.25);
  background: rgba(167, 139, 250, 0.08);
  color: var(--text);
  padding: 0.25rem 0.6rem;
  font-size: 0.82rem;
  cursor: pointer;
}

.chip.active {
  border-color: rgba(167, 139, 250, 0.6);
  background: rgba(167, 139, 250, 0.22);
  box-shadow: 0 0 22px rgba(167, 139, 250, 0.18);
}

.lab-tiles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.9rem;
}

.lab-tile {
  display: block;
  text-decoration: none;
  padding: 1rem 1.05rem;
  border-radius: 14px;
  border: 1px solid rgba(167, 139, 250, 0.35);
  background: rgba(10, 8, 18, 0.72);
  box-shadow: var(--shadow);
  transition: transform 140ms ease, border-color 140ms ease, background 140ms ease;
}

.lab-tile:hover {
  transform: translateY(-2px);
  border-color: rgba(167, 139, 250, 0.6);
  background: rgba(12, 9, 22, 0.85);
}

.tile-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.75rem;
}

.tile-head h3 {
  margin: 0;
  color: #efe8ff;
}

.tile-badge {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.18rem 0.5rem;
  border-radius: 999px;
  border: 1px solid rgba(167, 139, 250, 0.28);
  background: rgba(167, 139, 250, 0.12);
  color: rgba(239, 232, 255, 0.92);
}

@media (max-width: 980px) {
  .hero-top,
  .hero-demo {
    grid-template-columns: 1fr;
  }

  .lab-tiles {
    grid-template-columns: 1fr;
  }
}