/* ========== Commercial / EdTech polish layer ========== */

:root {
  --font-sans: ui-sans-serif, system-ui, -apple-system, "PingFang SC", "Microsoft YaHei",
    "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --font-serif: var(--font-sans);
  --font-mono: ui-monospace, "SF Mono", Menlo, "JetBrains Mono", monospace;

  /* Type scale (rem, base 16px) */
  --text-2xs: 0.6875rem; /* 11px — meta labels */
  --text-xs: 0.8125rem; /* captions */
  --text-sm: 0.875rem; /* UI chrome */
  --text-base: 1rem; /* 16px — body */
  --text-md: 1.0625rem; /* 17px — lead prose */
  --text-lg: 1.125rem; /* 18px — emphasis */
  --text-xl: 1.375rem; /* 22px — notebook titles */
  --text-2xl: 1.625rem;
  --text-3xl: 1.875rem;
  --text-display: 1.25rem;

  /* Math & viz (shared ch5–12) */
  --font-math: "STIX Two Math", "Cambria Math", Georgia, serif;
  --text-math: 1.125rem; /* 18px — inline formulas */
  --text-math-hero: 1.1875rem; /* 19px — primary equation line */
  --text-math-frac-num: 1.0625rem; /* 17px */
  --text-math-frac-den: 1rem; /* 16px */
  --text-viz-caption: var(--text-xs); /* diagram captions */
  --text-viz-label: var(--text-2xs); /* axis / chip labels in SVG */
  --leading-tight: 1.3;
  --leading-snug: 1.5;
  --leading-normal: 1.75;
  --leading-relaxed: 1.85;

  /* Brand palette — single source (overrides styles.css) */
  --ink: #202724;
  --muted: #5d6661;
  --line: #dfe5e1;
  --panel: #ffffff;
  --paper: #ffffff;
  --accent: #176b62;
  --accent-strong: #12584f;
  --accent-hover: #0f766e;
  --accent-soft: #edf5f2;
  --accent-muted: #b9d6cd;
  --amber: #b45309;
  --red: #c2410c;
  --blue: #2563eb;
  --green: #15803d;

  /* Spacing (8px rhythm) */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;

  --measure-prose: 40em;
  --measure-narrow: 34em;

  --content-max: 1180px;
  --radius-sm: 6px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 8px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04), 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 16px rgba(15, 23, 42, 0.06), 0 8px 24px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 12px 40px rgba(15, 23, 42, 0.08), 0 24px 48px rgba(15, 23, 42, 0.04);
  --surface-base: #ffffff;
  --surface-raised: #ffffff;
  --surface-inset: #f3f6f4;
  --ink-secondary: #46534c;
  --lab-bg: #ffffff;
  --lab-surface: #ffffff;
  --lab-border: #dbe3de;
  --lab-text: #202724;
  --lab-muted: #58665e;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 400;
  line-height: var(--leading-normal);
  color: var(--ink);
  background-color: var(--surface-base);
  background-image: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  font-feature-settings: "kern" 1;
}

h1,
h2,
h3,
h4,
.section-header h2,
.hero-copy h2,
.map-toolbar h2,
.comparison-card h3,
.notebook-header h3,
.step-detail-title {
  font-family: var(--font-serif);
  font-weight: 700;
  letter-spacing: 0;
  text-wrap: balance;
}

p {
  margin: 0 0 0.75em;
}

p:last-child {
  margin-bottom: 0;
}

strong {
  font-weight: 600;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 300;
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  background: var(--ink);
  color: #fff;
  font-weight: 600;
  text-decoration: none;
  transition: top 0.2s var(--ease-out);
}

.skip-link:focus {
  top: 12px;
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ----- Site header ----- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: #fff;
  border-bottom: 1px solid var(--line);
  box-shadow: none;
}

.site-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  max-width: calc(var(--content-max) + 72px);
  margin: 0 auto;
  padding: 14px clamp(16px, 3vw, 36px) 12px;
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.site-brand-mark {
  flex-shrink: 0;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: var(--accent);
  color: #fff;
  font-size: var(--text-sm);
  font-weight: 800;
  letter-spacing: 0;
  box-shadow: none;
}

.site-brand .eyebrow {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0;
  color: var(--accent-strong);
}

.site-title {
  margin: 4px 0 0;
  font-family: var(--font-serif);
  font-size: var(--text-display);
  line-height: var(--leading-tight);
  font-weight: 700;
  color: var(--ink);
}

.site-header-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
  font-size: var(--text-sm);
  color: var(--muted);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}

.progress-label {
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--accent-strong);
}

.meta-divider {
  opacity: 0.4;
}

.learning-progress {
  height: 3px;
  background: var(--surface-inset);
}

.learning-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent) 0%, #14b8a6 100%);
  transition: width 0.15s var(--ease-out);
}

/* ----- Layout shell ----- */

.site-main {
  max-width: calc(var(--content-max) + 72px);
  margin: 0 auto;
  padding: 0 clamp(16px, 3vw, 36px);
}

.section-nav-sticky {
  top: var(--header-height, 76px);
  max-width: calc(var(--content-max) + 72px);
  margin: 0 auto;
  padding-left: clamp(16px, 3vw, 36px);
  padding-right: clamp(16px, 3vw, 36px);
  background: #fff;
  border-bottom: none;
  border-radius: 0;
  box-shadow: none;
}

.section-link {
  border-radius: 0;
  border: 0;
  border-bottom: 2px solid transparent;
  padding: 10px 12px;
  background: transparent;
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0;
  transition: all 0.18s var(--ease-out);
}

.section-link.is-active {
  background: transparent;
  border-bottom-color: var(--accent);
  color: var(--accent-strong);
  box-shadow: none;
}

.section-link.is-visited:not(.is-active) {
  border-color: var(--accent-muted);
  color: var(--accent-strong);
}

/* ----- Sections: editorial rhythm ----- */

.chapter-section,
.hero-section {
  margin: 0;
  padding: var(--space-12) 0;
  border: none;
  border-radius: 0;
  background: transparent;
  border-bottom: 1px solid rgba(226, 232, 240, 0.75);
}

.chapter-section:nth-of-type(even) {
  background: transparent;
  box-shadow: none;
}

.reveal-section {
  opacity: 1;
  transform: none;
}

.reveal-section.is-visible {
  opacity: 1;
  transform: none;
}

.section-header {
  margin-bottom: 32px;
  max-width: var(--measure-prose);
}

.section-header .eyebrow {
  display: inline-block;
  margin-bottom: 10px;
  padding: 0;
  border-radius: 0;
  background: transparent;
  border: 0;
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0;
  text-transform: none;
  color: var(--accent-strong);
}

.section-header h2 {
  margin: 0;
  font-size: var(--text-2xl);
  line-height: var(--leading-tight);
}

.section-header p:not(.eyebrow) {
  margin: 12px 0 0;
  max-width: var(--measure-narrow);
  font-size: var(--text-md);
  line-height: var(--leading-normal);
  color: var(--ink-secondary);
}

/* ----- Hero ----- */

.hero-section {
  display: block;
  max-width: none;
  padding-top: var(--space-8);
  padding-bottom: var(--space-8);
  border-bottom: 1px solid rgba(226, 232, 240, 0.85);
}

.hero-copy h2 {
  margin: 0 0 16px;
  font-size: var(--text-3xl);
  line-height: var(--leading-tight);
}

.hero-copy p {
  margin: 0 0 14px;
  font-size: var(--text-md);
  line-height: var(--leading-normal);
  color: var(--ink-secondary);
  max-width: 56em;
}

.hero-copy p strong {
  color: var(--ink);
  font-weight: 600;
}

.hero-goals {
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.hero-goals li {
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr);
  align-items: baseline;
  gap: 12px;
  padding: 4px 0;
  border-radius: 0;
  background: transparent;
  border: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
  color: var(--ink-secondary);
  box-shadow: none;
}

.hero-goals strong {
  flex-shrink: 0;
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0;
  color: var(--accent-strong);
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.hero-metric {
  padding: 16px 12px;
  border-radius: var(--radius-md);
  background: var(--surface-raised);
  border: 1px solid var(--line);
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.hero-metric span {
  display: block;
  font-family: var(--font-serif);
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--accent-strong);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.hero-metric em {
  display: block;
  margin-top: 8px;
  font-style: normal;
  font-size: var(--text-xs);
  color: var(--muted);
  font-weight: 500;
  letter-spacing: 0;
}

.hero-formula {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: var(--space-5);
  padding: 10px 18px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent-soft) 0%, #fff 100%);
  border: 1px solid var(--accent-muted);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0;
  color: var(--accent-strong);
  line-height: var(--leading-snug);
  box-shadow: var(--shadow-sm);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-top: var(--space-6);
}

.story-quote {
  margin: 0;
  padding: 24px;
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-lg);
  background: var(--surface-raised);
  box-shadow: var(--shadow-md);
  font-size: 15px;
  line-height: 1.7;
}

/* ----- Cards & callouts ----- */

.knowledge-card,
.insight-callout,
.worked-result-badge,
.comparison-card {
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.knowledge-card {
  border-color: var(--accent-muted);
  background: linear-gradient(135deg, var(--accent-soft) 0%, #fff 80%);
  transition: box-shadow 0.2s var(--ease-out);
}

.knowledge-card:hover {
  box-shadow: var(--shadow-md);
}

.insight-callout {
  border-radius: var(--radius-md);
  border-left-width: 3px;
}

.dual-track-block {
  gap: 24px;
}

.advanced-path {
  border-style: solid;
  border-color: var(--line);
  border-radius: var(--radius-md);
  background: var(--surface-raised);
}

.minimax-advanced .advanced-body {
  padding-top: 4px;
  min-width: 0;
  overflow: hidden;
}

.dual-track-block.minimax-layout {
  grid-template-columns: 1fr;
}

.minimax-advanced {
  min-width: 0;
  max-width: 100%;
}

.minimax-compare-table {
  width: 100%;
  table-layout: fixed;
}

.minimax-compare-table th,
.minimax-compare-table td {
  word-break: break-word;
  white-space: normal;
  font-size: 12px;
  line-height: 1.45;
  vertical-align: top;
}

.advanced-mini-panel .table-wrap.compact {
  margin-top: 0;
  overflow-x: auto;
  max-width: 100%;
}

.advanced-mini-tabs {
  display: flex;
  gap: 6px;
  margin-bottom: 12px;
}

.advanced-mini-tab {
  flex: 1;
  padding: 7px 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--surface-inset);
  color: var(--muted);
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
}

.advanced-mini-tab.is-active {
  background: var(--accent-soft);
  border-color: var(--accent-muted);
  color: var(--accent-strong);
}

.advanced-mini-panel {
  min-height: 0;
}

.advanced-mini-panel .algo-steps {
  margin: 0;
  padding-left: 18px;
}

.advanced-mini-panel p {
  margin: 0;
  line-height: 1.65;
  color: var(--ink-secondary);
}

/* ----- Chapter algo tabs ----- */

.chapter-algo-tabs {
  background: var(--surface-inset);
  border: none;
  border-radius: var(--radius-lg);
  padding: 5px;
}

.chapter-algo-tab {
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 13px;
}

.chapter-algo-tab.is-active {
  border-color: transparent;
  box-shadow: var(--shadow-sm);
}

/* ----- Lab workspace ----- */

.lab-section {
  margin: 36px 0 40px;
  padding: 24px 0 8px;
  border: none;
  border-top: 1px solid var(--line);
  border-radius: 0;
  background: var(--lab-bg);
  color: var(--lab-text);
  overflow: visible;
  box-shadow: none;
}

.lab-section .section-header {
  padding: 0;
  max-width: none;
}

.lab-section .section-header h2 {
  margin-bottom: 8px;
}

.lab-section .section-header p {
  max-width: 720px;
  margin-bottom: 0;
  line-height: 1.55;
}

.lab-section .eyebrow {
  background: transparent;
  color: var(--accent-strong);
}

.lab-section h2 {
  color: var(--ink);
}

.lab-section .section-header p,
.lab-hint {
  color: var(--lab-muted);
}

.lab-section .app-shell {
  padding: 16px 0 24px;
}

.lab-section .visual-workspace,
.lab-section .panel {
  background: var(--lab-surface);
  border-color: var(--lab-border);
  box-shadow: none;
  color: var(--lab-text);
}

.lab-section .map-toolbar p,
.lab-section .step-copy,
.lab-section .panel h3,
.lab-section .lane-label,
.lab-section .range-label,
.lab-section .legend,
.lab-section .tech-details summary,
.lab-section .advanced-path summary {
  color: var(--lab-muted);
}

.lab-section .map-toolbar h2,
.lab-section .panel h2,
.lab-section .narrative-lead,
.lab-section .processing-card strong,
.lab-section .metrics dd {
  color: var(--ink);
}

.lab-section .tab {
  background: transparent;
  border-color: transparent;
  border-bottom: 2px solid transparent;
  border-radius: 0;
  color: var(--lab-muted);
  font-weight: 600;
}

.lab-section .tab[aria-selected="true"] {
  background: transparent;
  border-color: transparent;
  border-bottom-color: var(--accent);
  color: var(--accent-strong);
}

.lab-section .tab.is-active {
  background: transparent;
  border-color: transparent;
  border-bottom-color: var(--accent);
  color: var(--accent-strong);
}

.lab-section .step-counter {
  background: var(--surface-inset);
  color: var(--lab-text);
  border: 1px solid var(--lab-border);
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.lab-section .campus-frame {
  margin: 10px 0;
  background: transparent;
  border: none;
}

.lab-section .map-canvas {
  max-height: none;
  background: #ffffff;
  border-color: #cbd5e1;
}

.lab-section .map-canvas--auto .kg-svg,
.lab-section .kg-canvas .kg-svg {
  max-height: none;
}

.lab-section .campus-svg .graph-node circle {
  fill: #ffffff;
  stroke: #64748b;
}

.lab-section .campus-svg .graph-node .node-id {
  fill: #0f172a;
}

.lab-section .campus-svg .graph-node .node-name {
  fill: #475569;
}

.lab-section .campus-svg .graph-weight {
  fill: #475569;
}

.lab-section .campus-svg .node-metric {
  fill: #0f766e;
  font-size: 10px;
  font-weight: 700;
}

.lab-section .campus-svg .graph-edge {
  stroke: #94a3b8;
}

.lab-section .campus-svg .graph-edge.in-final,
.lab-section .campus-svg .graph-edge.in-path {
  stroke: #15803d;
}

.lab-section .campus-svg .graph-node.is-current circle {
  stroke: #b45309;
  fill: #fffbeb;
}

.lab-section .campus-svg .graph-node.is-frontier circle {
  fill: #eff6ff;
  stroke: #2563eb;
}

.lab-section .campus-svg .graph-node.is-visited circle {
  fill: #f1f5f9;
  stroke: #64748b;
}

.lab-section .campus-svg .graph-node.is-final circle {
  fill: #dcfce7;
  stroke: #15803d;
}

.lab-section input[type="range"] {
  accent-color: var(--accent);
  min-height: 28px;
  cursor: pointer;
}

.lab-section .playback {
  position: relative;
  z-index: 2;
}

.lab-section .range-label {
  color: var(--lab-muted);
}

.lab-section .range-label input {
  pointer-events: auto;
}

.lab-section .icon-button,
.lab-section .ghost-button {
  background: rgba(255, 255, 255, 0.06);
  border-color: var(--lab-border);
  color: var(--lab-text);
}

.lab-section .primary-button {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: 700;
}

.lab-section .metrics div {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--lab-border);
}

.lab-section .step-narrative,
.lab-section .step-panel .narrative-lead {
  background: #f8f7ed;
  border-color: #d8cfa5;
  color: #635016;
}

.lab-section .processing-card {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--lab-border);
}

.lab-section .pill-list span,
.lab-section .frontier-structure .queue-item {
  background: rgba(255, 255, 255, 0.06);
  border-color: var(--lab-border);
  color: var(--lab-text);
}

.lab-section pre,
.lab-section code {
  color: var(--lab-text);
}

.lab-section .advanced-path,
.lab-section .tech-details {
  border-color: var(--lab-border);
  background: rgba(255, 255, 255, 0.03);
}

/* ----- Buttons & focus ----- */

button,
a.hero-cta,
a.notebook-cta,
.lab-cta {
  transition: background 0.15s var(--ease-out), border-color 0.15s var(--ease-out),
    transform 0.12s var(--ease-out), box-shadow 0.15s var(--ease-out);
}

button:active:not(:disabled) {
  transform: scale(0.98);
}

button:focus-visible,
a:focus-visible,
.section-link:focus-visible,
.tab:focus-visible,
.chapter-algo-tab:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.primary-button,
.ghost-button,
.icon-button,
.lab-cta {
  font-weight: 600;
}

.primary-button {
  border-radius: var(--radius-md);
  box-shadow: 0 1px 2px rgba(13, 107, 98, 0.18);
  transition: background 0.2s var(--ease-out), border-color 0.2s var(--ease-out),
    box-shadow 0.2s var(--ease-out), transform 0.15s var(--ease-out);
}

.primary-button:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  box-shadow: 0 4px 14px rgba(13, 107, 98, 0.28);
  transform: translateY(-1px);
}

.ghost-button {
  border-radius: var(--radius-md);
  transition: background 0.2s var(--ease-out), border-color 0.2s var(--ease-out),
    color 0.2s var(--ease-out);
}

.ghost-button:hover {
  background: var(--accent-soft);
  border-color: var(--accent-muted);
  color: var(--accent-strong);
}

.lab-cta {
  border-radius: var(--radius-md);
  border-color: var(--accent-muted);
}

.lab-cta:hover {
  background: var(--accent-soft);
  box-shadow: var(--shadow-sm);
}

/* ----- Footer ----- */

.site-footer {
  margin-top: var(--space-12);
  padding: 40px clamp(16px, 3vw, 36px);
  background: var(--surface-base);
  border-top: 1px solid var(--line);
}

.site-footer a { color: var(--accent-strong); text-underline-offset: 3px; }

.site-footer-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  text-align: center;
}

.footer-brand {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.footer-links {
  margin: 12px 0;
}

.footer-links a {
  color: var(--accent-strong);
  font-weight: 600;
  text-decoration: none;
}

.footer-links a:hover {
  text-decoration: underline;
}

.footer-copy {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

/* ----- Scroll & map frames ----- */

[id] {
  scroll-margin-top: 104px;
}

.worked-map-slot,
.campus-map-static,
#reprCampusMap {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.campus-legend-inline {
  padding: 8px 12px;
  border-radius: var(--radius-md);
  background: var(--surface-raised);
  border: 1px solid var(--line);
}

/* ----- Onboarding polish ----- */

.onboarding-card {
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

.onboarding-card h2 {
  font-family: var(--font-serif);
}

/* ----- Mirror & comparison ----- */

.mirror-section {
  padding-bottom: 56px;
}

.comparison-ladder article {
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s var(--ease-out), transform 0.2s var(--ease-out);
}

.comparison-ladder article:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.mirror-cards blockquote {
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

/* ----- Responsive ----- */

@media (max-width: 900px) {
  .site-header-bar {
    flex-wrap: nowrap;
    gap: 10px;
  }

  .site-header-meta {
    width: auto;
    justify-content: flex-end;
  }

  .site-header-meta .progress-label,
  .site-header-meta .meta-divider,
  .site-header-meta .meta-reading { display: none; }

  .site-brand { gap: 10px; }
  .site-brand-mark { width: 34px; height: 34px; }
  .site-title { font-size: 16px; line-height: 1.5; }
  .site-brand .eyebrow { font-size: 12px; }
  .hub-link { margin: 0; min-height: 44px; white-space: nowrap; }

  .hero-section {
    grid-template-columns: 1fr;
    padding-top: 28px;
  }

  .hero-metrics {
    grid-template-columns: repeat(3, 1fr);
  }

  .lab-section {
    margin-left: 0;
    margin-right: 0;
    border-radius: 0;
  }

  .lab-section .section-header,
  .lab-section .app-shell {
    padding-left: 20px;
    padding-right: 20px;
  }

  .section-nav-sticky {
    top: 62px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal-section {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .learning-progress-fill,
  button,
  .comparison-ladder article {
    transition: none;
  }
}

/* ----- Vibe Coding notebook cells ----- */

.hero-notebook-preview {
  display: grid;
  gap: 12px;
  padding: 20px;
  border-radius: var(--radius-lg, 12px);
  border: 1px solid var(--line);
  background: var(--panel-elevated, #fafbfc);
  box-shadow: var(--shadow-soft, 0 8px 24px rgba(15, 23, 42, 0.06));
}

.hero-notebook-preview .preview-cell {
  margin: 0;
  padding: 12px 14px;
}

.vibe-notebook-host + .vibe-notebook-host {
  margin-top: 40px;
}

.vibe-notebook,
.vibe-module-host .vibe-notebook,
.vibe-notebook-body,
.vibe-cell-pair,
.vibe-cell,
.vibe-prompt,
.vibe-output,
.algo-notebook {
  min-width: 0;
  max-width: 100%;
}

.vibe-notebook-body,
.vibe-cell .cell-body,
.vibe-cell pre,
.vibe-output .cell-body {
  overflow-x: auto;
  overflow-wrap: anywhere;
  word-break: break-word;
}

.vibe-notebook,
.vibe-module-host .vibe-notebook {
  display: grid;
  gap: 24px;
}

.algo-notebook {
  padding: 0;
  border-radius: 0;
  border: 0;
  background: transparent;
  box-shadow: none;
}

.notebook-header {
  margin-bottom: 12px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.notebook-header h3 {
  margin: 0 0 8px;
  font-size: var(--text-xl);
  line-height: var(--leading-tight);
}

.notebook-subtitle {
  margin: 0;
  color: var(--muted);
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
}

.vibe-cell-pair {
  display: grid;
  gap: 12px;
}

.vibe-cell-pair + .vibe-cell-pair {
  margin-top: 8px;
  padding-top: 24px;
  border-top: 1px dashed var(--line);
}

.vibe-cell {
  border-radius: 0;
}

.vibe-prompt {
  overflow: hidden;
}

.vibe-output {
  overflow: visible;
}

.vibe-prompt {
  border: 0;
  background: transparent;
  box-shadow: none;
}

.vibe-output {
  border: 0;
  background: transparent;
}

.cell-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0;
}

.cell-index {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--accent-strong, #0a524c);
}

.cell-label {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0;
  text-transform: none;
  color: #64748b;
}

.prompt-body {
  margin: 12px 0;
  max-width: 48em;
  display: grid;
  gap: 14px;
}

.vibe-prompt-text {
  color: #1e293b;
  font-family: var(--font-sans);
  font-size: var(--text-md);
  font-weight: 400;
  line-height: var(--leading-relaxed);
  letter-spacing: 0;
}

.vibe-prompt-spec {
  padding: 14px 16px;
  border-radius: 10px;
  background: #eef2ff;
  border: 1px solid #c7d2fe;
}

.vibe-prompt-spec-label {
  display: block;
  margin-bottom: 8px;
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0;
  text-transform: none;
  color: #3730a3;
}

.vibe-prompt-spec-body {
  margin: 0;
  max-height: none;
  overflow: visible;
  color: #1e1b4b;
  background: transparent;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.7;
  white-space: pre-wrap;
  word-break: break-word;
}

.vibe-prompt .vibe-prompt-spec-body,
.vibe-prompt pre {
  margin: 0;
  max-height: none;
  overflow: visible;
  background: transparent;
  border-radius: 0;
}

.vibe-tip {
  margin: 0 0 16px;
  padding: 8px 12px;
  border-radius: 0;
  background: #f4f7f5;
  border: 0;
  border-left: 2px solid var(--accent-muted);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
  color: #134e4a;
}

.vibe-tip-label {
  display: inline-block;
  margin-right: 8px;
  padding: 0;
  border-radius: 0;
  background: transparent;
  color: var(--accent-strong);
  font-size: var(--text-2xs);
  font-weight: 600;
  letter-spacing: 0;
  vertical-align: middle;
}

.prompt-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding: 0 0 16px;
}

.copy-prompt-btn {
  min-height: 42px;
  padding-inline: 18px;
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0;
  background: #fff;
  border: 1px solid var(--line);
  color: var(--ink-secondary);
  box-shadow: none;
}

.copy-prompt-btn:hover { background: var(--surface-inset); border-color: #9bb4aa; color: var(--accent-strong); }

.prompt-copy-hint {
  margin: 0 0 12px;
  padding: 10px 12px;
  font-size: 14px;
  line-height: 1.6;
  color: #475569;
  background: #f8fafc;
  border-radius: 8px;
  border-left: 3px solid var(--accent, #0d6b62);
}

.prompt-copy-hint strong {
  color: #0f172a;
}

/* Interactive demo: full width, not squeezed in right column */
.vibe-cell-pair--interactive {
  grid-template-columns: 1fr !important;
  gap: 20px;
}

.vibe-cell-pair--interactive .vibe-output .output-body {
  padding-top: 4px;
}

.worked-player,
.worked-player-main {
  display: flex;
  flex-direction: column;
  gap: 14px;
  min-width: 0;
}

.worked-result-badge {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 14px;
  padding: 10px 14px;
}

.worked-result-badge .badge-label {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0;
  color: var(--muted);
}

.worked-controls-bar {
  position: relative;
  top: auto;
  z-index: 2;
  margin: 0;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  background: #ffffff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
}

@media (min-width: 900px) {
  .worked-controls-bar {
    position: sticky;
    top: 88px;
  }
}

.worked-controls-bar .step-btn {
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
}

.worked-controls-bar .step-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.worked-range-label {
  display: block;
  font-size: var(--text-xs);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
  margin-bottom: 4px;
  text-align: center;
}

/* Step panel: strip + detail card (replaces cramped table) */
.worked-step-panel {
  display: grid;
  gap: 12px;
  min-width: 0;
  overflow: visible;
}

.step-nav-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  overflow: visible;
  padding: 6px 4px 14px;
}

.step-nav-btn {
  flex: 0 0 auto;
  display: grid;
  gap: 2px;
  min-width: 64px;
  padding: 8px 10px 10px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: #1e293b;
  cursor: pointer;
  scroll-snap-align: center;
  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s;
}

.step-nav-btn:hover {
  border-color: var(--accent-muted);
  background: var(--accent-soft);
}

.step-nav-btn.is-done {
  border-color: #bbf7d0;
  background: #f0fdf4;
}

.step-nav-btn.is-active {
  border-color: var(--accent);
  background: var(--accent-soft);
  box-shadow: 0 0 0 2px rgba(13, 107, 98, 0.15);
}

.step-nav-num {
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: #64748b;
}

.step-nav-btn.is-active .step-nav-num {
  color: var(--accent-strong);
}

.step-nav-label {
  font-size: var(--text-xs);
  font-weight: 600;
  line-height: var(--leading-tight);
  white-space: normal;
  overflow-wrap: anywhere;
  color: #334155;
}

.step-detail-card {
  padding: 18px 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: #fff;
  box-shadow: none;
}

.step-detail-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.step-detail-title {
  margin: 0;
  font-size: var(--text-lg);
  font-weight: 700;
  line-height: var(--leading-tight);
  color: var(--accent-strong);
}

.step-detail-index {
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--surface-inset);
}

.step-detail-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px 16px;
  margin: 0;
}

.detail-field {
  margin: 0;
}

.detail-field.detail-wide {
  grid-column: 1 / -1;
}

.detail-field dt {
  margin: 0 0 6px;
  font-size: var(--text-2xs);
  font-weight: 600;
  letter-spacing: 0;
  text-transform: none;
  color: var(--muted);
}

.detail-field dd {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
  color: #1e293b;
}

.detail-field dd strong {
  font-family: var(--font-serif);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--accent-strong);
}

.detail-field dd span {
  color: var(--muted);
}

.detail-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.detail-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #f8fafc;
  font-size: var(--text-sm);
  font-weight: 600;
  line-height: 1.3;
}

.detail-tag em {
  font-style: normal;
  font-size: var(--text-2xs);
  font-weight: 500;
  color: var(--muted);
}

.detail-tag.is-next {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.detail-tag.empty {
  color: var(--muted);
  font-weight: 600;
}

.detail-tag-badge {
  font-style: normal;
  font-size: 10px;
  font-weight: 800;
  padding: 2px 6px;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
}

.step-detail-reason {
  margin: 16px 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: var(--text-sm);
  line-height: var(--leading-normal);
  color: #475569;
}

.notebook-worked .worked-step-panel {
  margin-top: 4px;
}

@media (max-width: 720px) {
  .step-detail-grid {
    grid-template-columns: 1fr;
  }

  .worked-controls-bar {
    top: 72px;
  }

  .worked-controls-bar .worked-range {
    order: 3;
    flex: 1 1 100%;
  }
}

.copy-prompt-btn.is-copied {
  background: #15803d;
  border-color: #15803d;
}

.output-body {
  padding: 20px;
}

.output-body .step-narrative {
  font-size: var(--text-md);
  line-height: var(--leading-normal);
  color: #1e293b;
}

.output-caption {
  margin: 0;
  padding: 4px 0;
  font-size: var(--text-viz-caption);
  line-height: var(--leading-snug);
  color: var(--ink-secondary);
}

.output-body .notebook-pseudo {
  margin-bottom: 14px;
  padding: 14px 16px;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.7;
  background: #0f172a;
  color: #e2e8f0;
  border-radius: 10px;
  overflow-x: auto;
}

.notebook-worked .dual-track-block,
.notebook-worked .notebook-focus-layout {
  gap: 12px;
}

.notebook-worked .advanced-path {
  margin-top: 8px;
}

.notebook-insight {
  margin: 0;
}

.learning-path-list {
  margin: 0;
  padding-left: 1.2rem;
  display: grid;
  gap: 14px;
}

.learning-path-list li {
  display: grid;
  gap: 6px;
  font-size: 15px;
  color: #111827;
}

.learning-path-list strong {
  font-size: 16px;
}

.learning-path-list span {
  color: #334155;
  font-size: 15px;
  line-height: 1.65;
}

.lab-cta-copy {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

.minimax-notebook-wrap {
  display: grid;
  gap: 12px;
}

.frontier-focus-slot {
  margin: 12px 0;
  padding: 12px;
  border-radius: 8px;
  background: #f8fafc;
  border: 1px dashed var(--line);
}

.focus-label {
  margin: 0 0 8px;
  font-size: 14px;
}

@media (max-width: 900px) {
  .hero-section {
    grid-template-columns: 1fr;
  }

  .hero-notebook-preview {
    order: -1;
  }

  .prompt-actions {
    flex-direction: row;
  }

  .prompt-actions .ghost-button,
  .prompt-actions .primary-button {
    width: auto;
    justify-content: center;
  }
}

/* ----- Responsive layout: maps, tables, lab, notebook ----- */

.map-canvas {
  width: 100%;
  aspect-ratio: 640 / 320;
  max-height: min(46vh, 440px);
  margin: 0 auto;
  padding: 10px 12px;
  border-radius: var(--radius-md);
  background: #f6f8f7;
  border: 1px solid var(--line);
  box-sizing: border-box;
}

/* 笔记本 / 步进演示内的图谱：含图例，不裁切 */
.worked-player .map-canvas,
.map-canvas--auto {
  aspect-ratio: auto;
  max-height: none;
  height: auto;
  overflow: visible;
  min-height: 0;
  padding-bottom: 16px;
}

.worked-player .map-canvas .kg-svg,
.map-canvas--auto .kg-svg {
  width: 100%;
  height: auto;
  display: block;
  max-height: none;
  aspect-ratio: unset;
}

.worked-player .demo-visual--rich {
  min-height: 0;
  overflow: visible;
  padding-bottom: 8px;
}

.worked-player .demo-detail {
  overflow: visible;
  padding-bottom: 4px;
}

/* 实验室：浅色工作区 + 深色文字，避免白卡片继承 lab 浅色字 */
.worked-player--lab {
  color: #1e293b;
}

.worked-player--lab .demo-visual--rich,
.worked-player--lab .worked-controls-bar,
.worked-player--lab .step-detail-card,
.worked-player--lab .logic-panel,
.worked-player--lab .step-nav-btn {
  color: #1e293b;
  background: #fff;
}

.worked-player--lab .rule-line {
  color: #1e293b;
  background: #ffffff;
}

.worked-player--lab .rule-line.is-fired {
  color: #0a524c;
  background: #ecfdf5;
}

.worked-player--lab .logic-panel h5,
.worked-player--lab .detail-field dt,
.worked-player--lab .step-detail-index,
.worked-player--lab .worked-range-label,
.worked-player--lab .step-nav-num {
  color: #64748b;
}

.worked-player--lab .detail-field dd,
.worked-player--lab .step-detail-reason,
.worked-player--lab .step-detail-summary,
.worked-player--lab .output-caption {
  color: #334155;
}

.worked-player--lab .step-detail-title {
  color: #0a524c;
}

.worked-player--lab .step-nav-btn.is-active {
  border-color: #0d6b62;
  background: #ecfdf5;
  color: #0a524c;
}

.worked-player--lab .step-nav-label,
.worked-player--lab .step-nav-num {
  color: #334155;
}

.worked-player--lab .step-nav-btn.is-active .step-nav-label,
.worked-player--lab .step-nav-btn.is-active .step-nav-num {
  color: #0a524c;
}

.lab-section .lab-panel .rule-line {
  color: #1e293b;
  background: #ffffff;
  border-color: #cbd5e1;
}

.lab-section .lab-panel .detail-field dt {
  color: #64748b;
}

.lab-section .lab-panel .detail-field dd {
  color: #1e293b;
}

.worked-player--lab .kg-legend {
  color: #475569;
}

.worked-player--lab .worked-controls-bar .step-btn {
  background: #ecfdf5;
  color: #0a524c;
}

.worked-player--lab .map-canvas--auto,
.worked-player--lab .kg-canvas {
  background: #fff;
}

.worked-player--lab .chart-canvas-wrap {
  background: #fff;
  border-color: #e2e8f0;
}

.worked-player .chart-canvas-wrap {
  overflow: visible;
}

.worked-player .chart-canvas-wrap canvas {
  max-height: min(42vh, 340px);
}

.map-canvas:not(.map-canvas--auto) .campus-svg:not(.kg-svg) {
  width: 100%;
  height: 100%;
  display: block;
}

.map-canvas--auto .campus-svg.kg-svg,
.worked-player .map-canvas .kg-svg {
  width: 100%;
  height: auto;
  max-height: none;
  display: block;
  overflow: visible;
}

.campus-frame.map-canvas,
.campus-frame .map-canvas {
  max-height: min(42vh, 360px);
}

.lab-section .map-canvas {
  max-height: min(42vh, 360px);
  background: #ffffff;
  border-color: #cbd5e1;
}

.lab-section .map-canvas:not(.map-canvas--auto):not(.kg-canvas) {
  width: min(100%, 680px);
  max-height: 340px;
}

@media (max-height: 760px) and (min-width: 900px) {
  .lab-section .map-canvas:not(.map-canvas--auto):not(.kg-canvas) {
    width: min(100%, 520px);
  }
}

#lab .tabs,
#lab .app-shell,
#lab .lab-panel,
#minimaxLabPanel {
  scroll-margin-top: 126px;
}

@media (max-width: 680px) {
  #lab .tabs,
  #lab .app-shell,
  #lab .lab-panel,
  #minimaxLabPanel {
    scroll-margin-top: 176px;
  }
}

.lab-section .worked-player .map-canvas,
.lab-section .map-canvas--auto,
.lab-section .kg-canvas {
  max-height: none;
}

.lab-section .map-canvas--auto .kg-svg,
.lab-section .kg-canvas .kg-svg {
  max-height: none;
}

.worked-map-slot.map-canvas {
  margin-bottom: 4px;
}

/* Tables: fit viewport, no forced horizontal drag */
.table-wrap {
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: #fff;
}

.table-wrap.compact {
  border-color: #e2e8f0;
}

.run-table.compact,
.comparison-table,
.minimax-compare-table {
  min-width: 0 !important;
  width: 100%;
  table-layout: fixed;
}

.comparison-table th,
.comparison-table td {
  white-space: normal;
  word-break: break-word;
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
}

.comparison-table th {
  font-weight: 600;
  letter-spacing: 0;
}

.comparison-table th:nth-child(1),
.comparison-table td:nth-child(1) {
  width: 14%;
}

.comparison-table th:nth-child(4),
.comparison-table td:nth-child(4) {
  width: 22%;
}

/* Minimax tree: scale to container */
.minimax-tree-host,
.minimax-notebook-wrap .minimax-tree-host {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #f8fafc;
  padding: 8px;
}

.game-tree-svg {
  width: 100%;
  min-width: 0 !important;
  height: auto;
  display: block;
}

/* Notebook: stack on all widths; interactive demos need full width */
.vibe-cell-pair {
  grid-template-columns: 1fr;
  gap: 16px;
}

@media (min-width: 1100px) {
  .vibe-cell-pair:not(.vibe-cell-pair--interactive):not(.vibe-cell-pair--text-only) {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
    gap: 20px;
    align-items: start;
  }
}

/* Lab: immersive width — stay within page, avoid 100vw clip */
@media (min-width: 1100px) {
  .lab-section {
    margin-left: 0;
    margin-right: 0;
    border-radius: var(--radius-xl);
  }

  .lab-section .app-shell {
    grid-template-columns: minmax(0, 1.45fr) minmax(300px, 0.55fr);
    gap: 22px;
    max-width: calc(var(--content-max) + 72px);
    margin: 0 auto;
    padding-left: clamp(18px, 2.6vw, 34px);
    padding-right: clamp(18px, 2.6vw, 34px);
  }
}

.app-shell {
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
}

@media (max-width: 1040px) {
  .app-shell {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .lab-section .app-shell {
    padding-left: 16px;
    padding-right: 16px;
  }

  .lab-section {
    margin-top: 28px;
  }

  .lab-section .section-header {
    padding: 18px 20px 0;
  }

  .lab-section .playback {
    align-items: stretch;
  }

  .lab-section .playback .primary-button,
  .lab-section .playback .ghost-button,
  .lab-section .playback .icon-button {
    min-width: 0;
    white-space: normal;
  }
}

/* ----- Typography sync: tables & code (all chapters) ----- */
.comparison-table,
.run-table.compact,
.run-table.compact th,
.run-table.compact td {
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
}

code,
pre,
.notebook-pseudo,
.vibe-prompt pre {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
}

/* Final mobile lab overrides must stay after the base playback rules. */
.playback[hidden],
.lab-section .playback[hidden] {
  display: none !important;
}

@media (max-width: 680px) {
  .lab-section .map-toolbar {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: start;
    gap: 6px 8px;
  }

  .lab-section .map-toolbar h2 {
    font-size: 16px;
    line-height: 1.2;
  }

  .lab-section .map-toolbar p {
    margin-top: 4px;
    font-size: 12px;
    line-height: 1.35;
  }

  .lab-section .step-counter {
    width: auto;
    min-width: 58px;
    min-height: 34px;
    font-size: 14px;
  }

  .lab-section .playback {
    grid-template-columns: 34px minmax(0, 1fr) 34px 52px;
    align-items: center;
    gap: 6px;
    margin-top: 8px;
    padding: 6px;
  }

  .lab-section .playback .ghost-button {
    grid-column: auto;
  }

  .lab-section .playback .range-label {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    gap: 8px;
    min-height: 28px;
  }

  .lab-section .playback input[type="range"] {
    min-height: 20px;
  }

  .lab-section .playback .primary-button,
  .lab-section .playback .ghost-button,
  .lab-section .playback .icon-button {
    min-height: 34px;
    padding: 4px 6px;
    white-space: nowrap;
  }

  .lab-section .playback .icon-button {
    font-size: 20px;
  }
}

.playback[hidden],
.lab-section .playback[hidden] {
  display: none !important;
}

@media (max-width: 680px) {
  .lab-section .playback {
    grid-template-columns: 34px minmax(0, 1fr) 34px 52px;
    align-items: center;
    gap: 6px;
    margin-top: 8px;
    padding: 6px;
  }

  .lab-section .playback .ghost-button {
    grid-column: auto;
  }

  .lab-section .playback .range-label {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    gap: 8px;
    min-height: 28px;
  }

  .lab-section .playback input[type="range"] {
    min-height: 20px;
  }

  .lab-section .playback .primary-button,
  .lab-section .playback .ghost-button,
  .lab-section .playback .icon-button {
    min-height: 34px;
    padding: 4px 6px;
    white-space: nowrap;
  }

  .lab-section .playback .icon-button {
    font-size: 20px;
  }

  .worked-player--lab .demo-visual--rich.kg-canvas,
  .worked-player--lab .map-canvas--auto,
  .worked-player--lab .kg-canvas,
  .lab-section .worked-player .map-canvas,
  .lab-section .map-canvas--auto,
  .lab-section .kg-canvas {
    max-height: min(48vh, 380px);
    overflow: auto;
  }

  .worked-player--lab .worked-controls-bar {
    gap: 6px;
    padding: 6px 8px;
  }

  .worked-player--lab .worked-controls-bar .step-btn {
    min-height: 32px;
    padding: 5px 7px;
  }

  .worked-player--lab .worked-range {
    flex-basis: 100%;
    gap: 6px;
  }

  .worked-player--lab .step-nav-strip {
    gap: 5px;
    max-height: 54px;
    overflow-y: auto;
    padding: 2px 0 6px;
  }

  .worked-player--lab .step-nav-btn {
    min-width: 44px;
    padding: 5px 6px;
  }

  .worked-player--lab .step-detail-card {
    max-height: min(18vh, 140px);
    overflow-y: auto;
    padding: 10px 12px;
  }

  .worked-player--lab .step-detail-head {
    margin-bottom: 8px;
  }

  .worked-player--lab .step-detail-title {
    font-size: var(--text-sm);
  }

  .worked-player--lab .step-detail-summary,
  .worked-player--lab .step-detail-reason {
    margin: 6px 0;
  }

  .lab-section .minimax-tree-host {
    max-height: 150px;
    margin: 0;
  }

  .lab-section .game-tree-svg {
    height: 140px;
    max-height: 140px;
  }

  .lab-section .minimax-lab-panel .step-narrative {
    max-height: 64px;
    overflow-y: auto;
  }

  .lab-section .minimax-lab-controls {
    gap: 6px;
    padding: 6px 8px;
  }

  .lab-section .minimax-lab-panel > .range-label {
    display: flex;
    align-items: center;
    gap: 8px;
    min-height: 28px;
  }
}

/* Lab compact mode: keep the full interaction visible inside one viewport. */
.worked-player--lab,
.worked-player--lab .worked-player-main {
  gap: 10px;
}

.worked-player--lab .demo-visual--rich {
  min-height: 0;
  max-height: none;
  padding: 12px 14px 16px;
  overflow: visible;
}

.worked-player--lab .demo-visual--rich.kg-canvas,
.worked-player--lab .map-canvas--auto,
.worked-player--lab .kg-canvas,
.lab-section .worked-player .map-canvas,
.lab-section .map-canvas--auto,
.lab-section .kg-canvas {
  max-height: none;
  overflow: visible;
}

.worked-player--lab .kg-wrap {
  display: grid;
  gap: 8px;
}

.worked-player--lab svg,
.worked-player--lab .arch-svg,
.worked-player--lab .td-svg,
.worked-player--lab .bellman-diagram-svg,
.worked-player--lab .mdp-booking-svg,
.worked-player--lab .kg-svg,
.worked-player--lab .mcts-svg,
.worked-player--lab .repr-landscape-svg,
.worked-player--lab .diffusion-svg,
.worked-player--lab .gan-sample-svg,
.worked-player--lab .activation-svg,
.worked-player--lab .xor-svg,
.worked-player--lab .clip-arch-mini {
  width: 100%;
  height: auto;
  min-height: 0;
  max-height: none;
  display: block;
}

/* Large graphs: scroll inside visual pane only */
.worked-player--lab .demo-visual--rich.kg-canvas,
.lab-section .worked-player .map-canvas.kg-canvas,
.lab-section .map-canvas--auto,
.lab-section .kg-canvas {
  max-height: min(58vh, 520px);
  overflow: auto;
}

.worked-player--lab .kg-canvas .kg-svg,
.lab-section .kg-canvas .kg-svg {
  max-height: none;
  height: auto;
}

.worked-player--lab .arch-figure,
.worked-player--lab .activation-chart-wrap,
.worked-player--lab .xor-demo-wrap,
.worked-player--lab .gan-sample-viz,
.worked-player--lab .diffusion-step-viz,
.worked-player--lab .repr-landscape-viz {
  padding: 8px;
}

.worked-player--lab .logic-demo-grid {
  gap: 8px;
}

.worked-player--lab .logic-panel {
  padding: 10px;
}

.worked-player--lab .rule-line {
  margin: 4px 0;
  padding: 6px 8px;
  line-height: 1.4;
}

.worked-player--lab .worked-controls-bar {
  gap: 8px;
  padding: 8px 10px;
  box-shadow: none;
}

.worked-player--lab .worked-controls-inline {
  margin-top: 0;
}

.worked-player--lab .worked-controls-bar .step-btn {
  min-height: 34px;
  padding: 6px 10px;
}

.worked-player--lab .worked-range {
  display: flex;
  flex: 1 1 180px;
  align-items: center;
  gap: 8px;
  min-width: 0;
}

.worked-player--lab .worked-range-label {
  flex: 0 0 auto;
  margin-bottom: 2px;
}

.worked-player--lab input[type="range"] {
  flex: 1 1 auto;
  min-height: 22px;
}

.worked-player--lab .worked-step-panel {
  gap: 8px;
}

.worked-player--lab .step-nav-strip {
  gap: 6px;
  padding: 3px 2px 8px;
}

.worked-player--lab .step-nav-btn {
  min-width: 64px;
  max-width: 132px;
  padding: 6px 8px;
  border-radius: 8px;
}

.worked-player--lab .step-detail-card {
  padding: 12px 14px;
}

.worked-player--lab .step-detail-head {
  margin-bottom: 10px;
}

.worked-player--lab .step-detail-title {
  font-size: var(--text-md);
}

.worked-player--lab .step-detail-summary,
.worked-player--lab .step-detail-reason {
  margin: 8px 0;
  line-height: 1.45;
}

.lab-section .legend {
  margin: 10px 0;
  gap: 8px;
}

.lab-section .playback {
  margin-top: 10px;
  padding: 10px;
  gap: 8px;
}

.lab-section .playback .primary-button,
.lab-section .playback .ghost-button,
.lab-section .playback .icon-button {
  min-height: 38px;
  padding: 6px 10px;
}

.lab-section .minimax-tree-host {
  margin: 10px 0;
  max-height: min(58vh, 520px);
  overflow: auto;
  padding: 8px;
}

.lab-section .game-tree-svg {
  height: auto;
  max-height: none;
}

.lab-section .minimax-lab-controls {
  margin-top: 8px;
  gap: 8px;
  padding: 8px 10px;
}

.lab-section .minimax-lab-panel .step-narrative {
  margin: 8px 0;
  padding: 10px 12px;
}

.lab-section .minimax-lab-panel > .range-label {
  margin-top: 8px;
}

.lab-section .minimax-lab-panel[hidden] {
  display: none !important;
}

@media (min-width: 900px) {
  .worked-player--lab .worked-player-main {
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
    grid-template-areas:
      "visual detail"
      "controls detail";
    align-items: start;
    gap: 10px 12px;
  }

  .worked-player--lab .demo-visual--rich {
    grid-area: visual;
  }

  .worked-player--lab .worked-controls-bar {
    position: relative;
    top: auto;
    grid-area: controls;
  }

  .worked-player--lab .demo-detail {
    grid-area: detail;
    align-self: start;
  }

  .worked-player--lab .step-nav-strip {
    max-height: 94px;
    overflow-y: auto;
  }

  .worked-player--lab .step-detail-card {
    max-height: min(48vh, 360px);
    overflow-y: auto;
  }

  .lab-section .minimax-lab-panel {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
    align-items: start;
    gap: 10px 12px;
  }

  .lab-section .minimax-tree-host {
    grid-row: 1 / span 3;
    margin: 0;
  }

  .lab-section .minimax-lab-panel .step-narrative {
    margin: 0;
  }

  .lab-section .minimax-lab-panel > .range-label {
    margin-top: 0;
  }
}

@media (max-height: 760px) and (min-width: 900px) {
  .worked-player--lab .demo-visual--rich.kg-canvas,
  .lab-section .worked-player .map-canvas,
  .lab-section .map-canvas--auto,
  .lab-section .kg-canvas {
    max-height: min(50vh, 440px);
  }

  .lab-section .minimax-tree-host {
    max-height: min(50vh, 440px);
  }
}

.worked-player--lab .map-canvas .kg-svg,
.worked-player--lab .demo-visual--rich .kg-svg,
.lab-section .worked-player .map-canvas .kg-svg {
  width: 100%;
  height: auto;
  min-height: 0;
  max-height: none;
  display: block;
}

@media (max-height: 760px) and (min-width: 900px) {
  .worked-player--lab .map-canvas .kg-svg,
  .worked-player--lab .demo-visual--rich .kg-svg,
  .lab-section .worked-player .map-canvas .kg-svg {
    max-height: none;
  }
}

@media (max-width: 680px) {
  .lab-section .playback {
    grid-template-columns: 38px minmax(0, 1fr) 38px 58px;
    padding: 8px;
  }

  .lab-section .playback .range-label {
    grid-column: 1 / -1;
  }

  .lab-section .playback .primary-button,
  .lab-section .playback .ghost-button,
  .lab-section .playback .icon-button {
    min-height: 36px;
    padding: 6px 8px;
  }

  .lab-section .playback .icon-button {
    font-size: 22px;
  }

  .worked-player--lab .demo-visual--rich.kg-canvas,
  .worked-player--lab .map-canvas--auto,
  .worked-player--lab .kg-canvas {
    max-height: min(52vh, 420px);
  }
}

/* Playback bar */
.playback {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  background: var(--surface-inset);
  border: 1px solid var(--line);
  flex-wrap: wrap;
  gap: 10px;
}

.lab-section .playback {
  background: rgba(255, 255, 255, 0.06);
  border-color: var(--lab-border);
}

.playback .range-label {
  flex: 1 1 160px;
  min-width: 0;
}

.playback input[type="range"] {
  width: 100%;
  max-width: 100%;
}

.playback .step-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-width: 0;
  min-height: 44px;
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface-base);
  color: var(--ink);
  font: inherit;
  white-space: nowrap;
  cursor: pointer;
}

.playback .step-btn:disabled {
  opacity: 0.45;
  cursor: default;
}

.playback #playPause {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.worked-controls-inline {
  position: relative;
  top: auto;
  flex-wrap: wrap;
  padding: 10px 12px;
  border-radius: var(--radius-md);
  background: #f1f5f9;
  border: 1px solid var(--line);
}

.worked-controls-inline .worked-range {
  flex: 1 1 180px;
  min-width: 0;
}

.worked-controls-inline input[type="range"] {
  width: 100%;
}

/* Pseudo code: collapsible feel, less scroll trap */
.notebook-pseudo,
.pseudo-compact {
  max-height: none;
  border-radius: var(--radius-sm);
  mask-image: none;
}

.notebook-pseudo:hover,
.pseudo-compact:hover {
  max-height: none;
  mask-image: none;
}

/* Section nav: wrap on desktop, scroll hint on mobile */
.section-nav-wrap {
  position: sticky;
  top: var(--header-height, 76px);
  z-index: 35;
  background: #fff;
  border-bottom: 1px solid var(--line);
  max-width: calc(var(--content-max) + 72px);
  margin: 0 auto;
  padding: 0 clamp(16px, 3vw, 36px);
}

.section-nav-wrap .section-nav-sticky {
  position: static;
  max-width: none;
  margin: 0;
  padding-left: 0;
  padding-right: 0;
  flex-wrap: nowrap;
  overflow-x: auto;
  gap: 4px;
}

.section-nav-scroll-hint {
  display: none;
}

.section-nav-sticky {
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.section-nav-sticky::-webkit-scrollbar {
  display: none;
}

@media (max-width: 899px) {
  .section-nav-wrap {
    position: sticky;
  }

  .section-nav-scroll-hint {
    display: none;
  }

  .section-nav-sticky {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-right: 0;
    box-shadow: 0 1px 0 rgba(15, 23, 42, 0.08);
  }

  .map-canvas:not(.map-canvas--auto) {
    max-height: min(40vh, 320px);
  }

  .algo-notebook {
    padding: 0;
  }
}

@media (min-width: 900px) {
  .section-nav-sticky {
    flex-wrap: nowrap;
    overflow-x: auto;
  }
}

@media (max-width: 1040px) {
  .lab-section .app-shell {
    grid-template-columns: 1fr !important;
  }

  .lab-section .visual-workspace {
    order: 1;
  }

  .lab-section .inspector {
    order: 2;
  }
}

@media (max-width: 680px) {
  .lab-section .app-shell {
    padding-left: 16px;
    padding-right: 16px;
  }

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

  .lab-section .playback {
    align-items: stretch;
  }

  .lab-section .playback .primary-button,
  .lab-section .playback .ghost-button,
  .lab-section .playback .icon-button {
    min-width: 0;
    white-space: normal;
  }
}