:root {
  color-scheme: dark;
  --bg: #0f151e;
  --surface: #161f2b;
  --surface-strong: #1c2735;
  --surface-soft: #111a25;
  --text: #eef4f7;
  --muted: #9cabb7;
  --line: #344252;
  --base: #6689b8;
  --asrr: #45b9a2;
  --residual: #ef8065;
  --context: #b2a4d2;
  --focus: #f1bd70;
  --gold-current: #e5aa3a;
  --gold-visited: #f1d18a;
  --gold-future: #8f7b55;
  --success: #55c6a8;
  --danger: #ef8d74;
  --shadow: 0 18px 42px rgb(0 0 0 / 0.24);
}

:root[data-theme="light"],
[data-explainer-root][data-theme="light"] {
  color-scheme: light;
  --bg: #f3f6f8;
  --surface: #ffffff;
  --surface-strong: #edf2f5;
  --surface-soft: #f8fafb;
  --text: #172230;
  --muted: #5b6875;
  --line: #cdd6de;
  --base: #3e628f;
  --asrr: #258f7c;
  --residual: #d85f45;
  --context: #8070a8;
  --focus: #9f6300;
  --gold-current: #a96500;
  --gold-visited: #ddb968;
  --gold-future: #9b8c70;
  --success: #237c69;
  --danger: #b84b35;
  --shadow: 0 16px 38px rgb(23 34 48 / 0.12);
}

* { box-sizing: border-box; }
html { min-width: 0; background: var(--bg); }
body {
  min-width: 0;
  margin: 0;
  overflow-x: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.45;
}
button, input { font: inherit; }
button { color: inherit; }
button:focus-visible, a:focus-visible, input:focus-visible, [tabindex]:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}
button:disabled { cursor: not-allowed; opacity: 0.48; }
h1, h2, p { margin: 0; letter-spacing: 0; }
h1 { font-size: 1.22rem; line-height: 1.2; }
h2 { font-size: 1.12rem; line-height: 1.25; }
a { color: inherit; }

.explainer-app {
  color-scheme: dark;
  display: grid;
  height: 100dvh;
  min-height: 100dvh;
  grid-template-rows: auto auto minmax(0, 1fr) auto;
  overflow: hidden;
}
[data-theme="light"] .explainer-app { color-scheme: light; }

.app-header {
  display: grid;
  min-height: 62px;
  grid-template-columns: minmax(150px, 1fr) auto minmax(150px, 1fr);
  align-items: center;
  gap: 20px;
  padding: 10px 22px;
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}
.back-link { display: inline-flex; align-items: center; gap: 9px; width: max-content; color: var(--muted); font-size: 0.83rem; font-weight: 700; text-decoration: none; }
.back-link:hover { color: var(--text); }
.app-title { display: flex; align-items: baseline; justify-content: center; gap: 10px; white-space: nowrap; }
.app-title strong { color: var(--asrr); font-size: 1.02rem; }
.app-title span { color: var(--muted); font-size: 0.78rem; }
.app-header > .icon-command { justify-self: end; }

.chapter-tabs {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-bottom: 1px solid var(--line);
  background: var(--surface-soft);
}
.chapter-tabs button {
  position: relative;
  display: flex;
  min-width: 0;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 12px;
  border: 0;
  border-right: 1px solid var(--line);
  background: transparent;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
}
.chapter-tabs button:last-child { border-right: 0; }
.chapter-tabs button span { color: var(--base); font-size: 0.67rem; }
.chapter-tabs button[aria-current="step"] { background: var(--surface-strong); color: var(--text); }
.chapter-tabs button[aria-current="step"]::after { position: absolute; right: 12%; bottom: -1px; left: 12%; height: 3px; background: var(--asrr); content: ""; }

.workbench {
  display: grid;
  min-height: 0;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 330px);
  gap: 14px;
  padding: 14px;
  overflow: hidden;
}
.stage-panel, .inspector {
  min-width: 0;
  min-height: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
}
.stage-panel { display: grid; grid-template-rows: auto minmax(0, 1fr); overflow: hidden; }
.panel-heading { display: flex; min-height: 72px; align-items: center; justify-content: space-between; gap: 18px; padding: 14px 18px; border-bottom: 1px solid var(--line); }
.explainer-app .panel-heading h1 { margin: 0; font-size: 1.25rem; line-height: 1.2; }
.explainer-app .inspector h2 { margin: 8px 0 0; font-size: 1.2rem; line-height: 1.3; }
.overline { margin-bottom: 5px; color: var(--muted); font-size: 0.66rem; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }
.evidence-label { flex: 0 0 auto; padding: 5px 8px; border: 1px solid currentColor; border-radius: 4px; font-size: 0.66rem; font-weight: 800; text-transform: uppercase; }
.evidence-label--illustrative { color: var(--context); }
.stage-viewport { position: relative; min-width: 0; min-height: 340px; overflow: auto; background: var(--surface-soft); }
.stage-fallback { display: block; width: 100%; min-width: 620px; height: 100%; min-height: 340px; }
.fallback-grid { fill: none; stroke: var(--line); stroke-width: 1; }
.fallback-base, .fallback-refined { fill: none; stroke-linecap: round; stroke-width: 8; }
.fallback-base { stroke: var(--base); }
.fallback-refined { stroke: var(--asrr); stroke-dasharray: 13 10; }
.fallback-residual { fill: none; stroke: var(--residual); stroke-linecap: round; stroke-width: 7; }
.fallback-error { fill: var(--residual); stroke: var(--surface); stroke-width: 5; }
.fallback-target { fill: none; stroke: var(--asrr); stroke-width: 5; }
.stage-message { position: absolute; right: 20px; bottom: 16px; padding: 8px 10px; border-radius: 4px; background: var(--surface); color: var(--muted); font-size: 0.8rem; }

.scene { display: flex; min-width: 620px; height: 100%; min-height: 0; flex-direction: column; padding: 14px 18px 16px; overflow: hidden; }
.scene-meta { display: flex; align-items: center; justify-content: space-between; gap: 16px; color: var(--muted); font-size: 0.67rem; font-weight: 800; letter-spacing: 0.06em; text-transform: uppercase; }
.diagram-wrap, .refinement-diagram { position: relative; flex: 1 1 0; height: 0; min-height: 0; }
.trajectory-svg { display: block; width: 100%; height: 100%; min-height: 0; }
.diagram-wrap > .trajectory-svg { position: absolute; inset: 0; }
.diagram-grid { fill: none; stroke: var(--line); stroke-width: 1; }
.target-zone { fill: color-mix(in srgb, var(--asrr) 9%, transparent); stroke: var(--asrr); stroke-dasharray: 7 5; stroke-width: 2; }
.target-marker .target-zone { fill: color-mix(in srgb, var(--base) 8%, transparent); stroke: var(--base); }
.target-marker .svg-label { fill: var(--base); }
.target-cross { fill: none; stroke: var(--base); stroke-width: 2; }
.target-marker--refined .target-zone, .target-marker--refined .target-cross { stroke: var(--asrr); }
.target-marker--refined .svg-label { fill: var(--asrr); }
.trajectory { fill: none; stroke-linecap: round; stroke-linejoin: round; stroke-width: 7; }
.trajectory--base { stroke: var(--base); }
.trajectory--refined { stroke: var(--asrr); }
.action-point { cursor: pointer; outline: none; }
.action-point circle { stroke: var(--surface); stroke-width: 4; }
.action-point text, .identity-links text { fill: var(--muted); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 18px; font-weight: 800; }
.point--base { fill: var(--base); }
.point--refined { fill: var(--asrr); }
.action-point.is-selected circle { stroke: var(--focus); stroke-width: 5; }
.error-pulse { fill: color-mix(in srgb, var(--residual) 18%, transparent); stroke: var(--residual); stroke-width: 3; }
.error-callout { fill: none; stroke: var(--residual); stroke-dasharray: 5 4; stroke-width: 2; }
.svg-callout { fill: var(--residual); font-size: 15px; font-weight: 800; }
.svg-label { fill: var(--asrr); font-size: 13px; font-weight: 800; }
.token-strip { display: grid; grid-template-columns: repeat(8, minmax(48px, 1fr)); gap: 6px; width: 100%; }
.action-token, .execution-token { display: flex; min-width: 0; min-height: 45px; flex-direction: column; align-items: center; justify-content: center; padding: 5px; border: 1px solid var(--line); border-radius: 4px; background: var(--surface); }
.action-token span, .execution-token span { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.75rem; font-weight: 800; }
.action-token small, .execution-token small { color: var(--muted); font-size: 0.59rem; }
.action-token.is-selected { border-color: var(--focus); box-shadow: inset 0 0 0 1px var(--focus); }
.recorded-evidence-chip { align-self: flex-end; margin-top: 10px; padding: 6px 9px; border: 1px solid var(--line); border-radius: 4px; background: var(--surface); color: var(--muted); font-size: 0.7rem; font-weight: 800; }

.proposal-layout, .refiner-flow, .execution-flow { display: grid; align-items: center; gap: 12px; margin: auto 0; }
.proposal-layout { grid-template-columns: 170px 44px minmax(0, 1fr); }
.frozen-policy-block, .flow-block, .context-block, .native-operator { display: flex; min-height: 90px; flex-direction: column; align-items: center; justify-content: center; padding: 12px; border: 1px solid var(--line); border-radius: 6px; background: var(--surface); text-align: center; }
.frozen-policy-block span, .flow-block span, .context-block span, .native-operator span, .block-label { color: var(--muted); font-size: 0.63rem; font-weight: 800; text-transform: uppercase; }
.frozen-policy-block strong, .flow-block strong, .context-block strong, .native-operator strong { margin: 5px 0; font-family: ui-serif, Georgia, serif; font-size: 1.16rem; }
.frozen-policy-block small, .flow-block small, .context-block small, .native-operator small { color: var(--muted); font-size: 0.64rem; }
.proposal-output { min-width: 0; }
.proposal-output .block-label { display: block; margin-bottom: 8px; }
.proposal-arrow, .flow-arrow { color: var(--muted); font-size: 1.4rem; font-weight: 800; text-align: center; }
.identity-links { width: 100%; height: 210px; overflow: visible; }
.identity-links .trajectory { stroke-width: 5; }

.refiner-flow { grid-template-columns: minmax(115px, 0.7fr) 35px minmax(165px, 1fr) 35px minmax(120px, 0.75fr); margin-bottom: 4px; }
.flow-stack { display: grid; min-width: 0; gap: 5px; }
.flow-block--base { border-color: var(--base); }
.flow-block--refiner { border-color: var(--asrr); }
.flow-block--residual { border-color: var(--residual); }
.context-block { min-height: 58px; border-color: var(--context); }
.flow-arrow--context { color: var(--context); font-size: 1rem; line-height: 1; }
.refinement-diagram { display: grid; grid-template-rows: minmax(0, 1fr) auto; }
.residual-arrow { fill: none; stroke: var(--residual); stroke-width: 3; }
.residual-arrow.is-selected { stroke-width: 6; }
.residual-arrow + polygon, #arrowhead polygon { fill: var(--residual); }

.execution-flow { grid-template-columns: minmax(120px, 0.8fr) 40px minmax(170px, 1.15fr) 40px minmax(120px, 0.8fr); }
.flow-block--refined { border-color: var(--asrr); }
.native-operator { border-color: var(--base); }
.horizon-panel { margin: auto 0; padding: 18px; border: 1px solid var(--line); border-radius: 6px; background: var(--surface); }
.horizon-labels { display: flex; justify-content: space-between; gap: 14px; margin-bottom: 10px; color: var(--muted); font-size: 0.68rem; font-weight: 800; }
.execution-tokens { display: grid; grid-template-columns: repeat(8, minmax(52px, 1fr)); gap: 7px; }
.execution-token.is-editable { border-color: var(--asrr); }
.execution-token.is-retained { border-style: dashed; color: var(--muted); }
.execution-token.is-executed { background: color-mix(in srgb, var(--asrr) 18%, var(--surface)); box-shadow: inset 0 -3px var(--asrr); }
.replan-marker { position: relative; height: 34px; margin-top: 8px; border-top: 1px solid var(--line); }
.replan-marker::before { position: absolute; top: -6px; left: calc((100% / 8) * var(--replan-step)); width: 2px; height: 26px; background: var(--residual); content: ""; }
.replan-marker span { position: absolute; top: 10px; left: min(calc((100% / 8) * var(--replan-step) + 7px), calc(100% - 48px)); color: var(--residual); font-size: 0.65rem; font-weight: 800; text-transform: uppercase; }

.metric-ribbon { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; margin: 12px 0; }
.metric-ribbon div { min-width: 0; padding: 9px 10px; border-left: 3px solid var(--asrr); background: var(--surface); }
.metric-ribbon strong { display: block; color: var(--asrr); font-size: 1rem; }
.metric-ribbon span { display: block; color: var(--muted); font-size: 0.61rem; }
.evidence-wall { display: grid; flex: 1; min-height: 0; gap: 10px; }
.evidence-wall.is-opening { grid-template-columns: minmax(0, 720px); place-content: center; }
.evidence-wall.is-expanded { grid-template-columns: repeat(5, minmax(120px, 1fr)); align-items: start; }

/* Four-chapter robot teaching system. */
.trajectory--history { stroke: var(--gold-current); stroke-width: 4; }
.trajectory--ideal { stroke: var(--base); stroke-width: 7; stroke-dasharray: 9 7; opacity: 0.95; }
.trajectory-legend { display: flex; flex-wrap: wrap; flex: 0 0 auto; gap: 10px 24px; margin: 10px 0 4px; color: var(--muted); font-size: 0.71rem; font-weight: 700; }
.trajectory-legend span { display: inline-flex; align-items: center; gap: 8px; }
.trajectory-legend span::before { display: block; width: 25px; border-top: 3px solid var(--gold-current); content: ""; }
.trajectory-legend .legend-ideal::before { border-color: var(--base); border-top-style: dashed; }
.trajectory-legend .legend-refined::before { border-color: var(--asrr); }
.action-point .point--history { fill: var(--gold-future); transition: fill 180ms ease, r 180ms ease; }
.action-point.is-visited .point--history { fill: var(--gold-visited); }
.action-point.is-current .point--history { fill: var(--gold-current); stroke: var(--text); stroke-width: 5; }
.action-point.is-current text { fill: var(--gold-current); }
.action-point.is-visited text { fill: var(--gold-visited); }
.action-point.is-future text { fill: var(--gold-future); }
.action-point--refined .point--history { fill: var(--asrr); }
.action-point--refined.is-visited .point--history { fill: color-mix(in srgb, var(--asrr) 50%, var(--surface)); }
.action-point--refined.is-current .point--history { fill: var(--asrr); }
.action-point--refined text, .action-point--refined.is-current text, .action-point--refined.is-visited text { fill: var(--asrr); }
.error-pulse, .error-callout, .svg-callout { opacity: 0; transition: opacity 180ms ease; }
.error-pulse.is-visible, .error-callout.is-visible, .svg-callout.is-visible { opacity: 1; }

.local-error-annotation { opacity: 0.55; }
.local-error-annotation.is-reached { opacity: 1; }
.local-error-annotation .error-callout, .local-error-annotation .svg-callout { opacity: 1; }
.miss-annotation { opacity: 0; }
.miss-annotation.is-reached { opacity: 1; }
.miss-annotation path { fill: none; stroke: var(--residual); stroke-width: 3; }
.miss-annotation text { fill: var(--residual); font-size: 14px; font-weight: 700; }
.robot-arm { color: var(--gold-current); pointer-events: none; }
.robot-servo-accent { fill: none; stroke: currentColor; stroke-width: 3; }
.robot-tool-center { fill: currentColor; }
.robot-arm--refined { color: var(--asrr); }
.robot-arm--ghost { color: var(--gold-current); opacity: 0.25; }
.robot-arm--ideal-ghost { color: var(--base); opacity: 0.3; }

.adaptation-compare {
  display: grid;
  flex: 1;
  min-height: 0;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 10px;
}
.adaptation-lane { display: grid; min-width: 0; min-height: 0; grid-template-rows: auto auto minmax(0, 1fr); overflow: hidden; border: 1px solid var(--line); border-radius: 7px; background: var(--surface); }
.adaptation-lane--asrr { border-color: color-mix(in srgb, var(--asrr) 65%, var(--line)); }
.lane-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; padding: 10px 12px; border-bottom: 1px solid var(--line); }
.lane-heading span { color: var(--muted); font-size: 0.63rem; font-weight: 800; text-transform: uppercase; }
.lane-heading strong { font-size: 0.86rem; }
.adaptation-lane--asrr .lane-heading strong { color: var(--asrr); }
.lane-flow { display: grid; grid-template-columns: minmax(85px, 1fr) auto minmax(95px, 1.1fr) auto minmax(72px, 0.85fr); align-items: center; gap: 5px; padding: 10px; }
.lane-flow > span { color: var(--muted); font-weight: 900; }
.mini-block { display: flex; min-height: 48px; min-width: 0; flex-direction: column; align-items: center; justify-content: center; padding: 7px; border: 1px solid var(--line); border-radius: 5px; color: var(--muted); font-size: 0.58rem; font-weight: 800; text-align: center; }
.mini-block small { display: block; margin-top: 3px; color: var(--residual); font-size: 0.51rem; }
.mini-block--policy { border-color: var(--base); color: var(--text); }
.mini-block--frozen { border-color: var(--base); }
.mini-block--proposal { border-color: var(--gold-current); color: var(--gold-current); }
.mini-block--refiner { border-color: var(--asrr); color: var(--asrr); }
.lane-trajectory { display: flex; min-height: 0; flex-direction: column; }
.lane-trajectory .trajectory-legend { justify-content: center; gap: 12px; margin: 3px 8px 0; font-size: 0.6rem; }
.interface-arm { display: block; flex: 1; width: 100%; height: 0; min-height: 0; }
.interface-arm .action-point text { font-size: 23px; }
.interface-arm .svg-label { font-size: 20px; }
.interface-ground { fill: none; stroke: var(--line); stroke-width: 2; }
.interface-action { fill: var(--gold-current); stroke: var(--surface); stroke-width: 5; }
.interface-action--refined { fill: var(--asrr); }

.residual-mode-row { display: grid; grid-template-columns: minmax(125px, 0.8fr) minmax(0, 1fr) minmax(100px, 0.65fr) minmax(175px, 1fr); align-items: center; gap: 8px; margin: 9px 0 4px; }
.residual-mode-row--A { grid-template-columns: minmax(125px, 0.8fr) minmax(150px, 1fr) minmax(175px, 1fr); }
.mode-pill, .policy-data, .refiner-node, .method-status { min-width: 0; padding: 8px 10px; border: 1px solid var(--line); border-radius: 5px; background: var(--surface); }
.mode-pill { display: flex; flex-direction: column; border-color: var(--asrr); }
.mode-pill strong { color: var(--asrr); font-size: 0.78rem; }
.mode-pill span, .policy-data span, .refiner-node span { color: var(--muted); font-size: 0.55rem; }
.policy-data { border-color: var(--context); }
.policy-data strong { display: block; overflow: hidden; margin-top: 2px; color: var(--context); font-size: 0.63rem; text-overflow: ellipsis; white-space: nowrap; }
.context-path { display: grid; min-width: 0; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 7px; }
.context-link { color: var(--context); font-size: 1.2rem; font-weight: 900; text-align: center; }
.refiner-node { border-color: var(--residual); text-align: center; }
.refiner-node strong { display: block; color: var(--residual); }
.method-status { display: flex; flex-wrap: wrap; gap: 5px; justify-content: flex-end; }
.method-status span { padding: 3px 6px; border: 1px solid var(--line); border-radius: 3px; color: var(--muted); font-size: 0.54rem; font-weight: 800; }
.arm-comparison { position: relative; }
.trajectory--ghost { opacity: 0.65; stroke-dasharray: 9 8; }
.moving-refined-point { fill: var(--asrr); stroke: var(--surface); stroke-width: 3; }
.policy-state-annotation rect { fill: var(--surface); stroke: var(--context); stroke-width: 1.5; }
.policy-state-annotation text { fill: var(--context); font-size: 24px; font-weight: 800; }
.policy-state-annotation .policy-state-detail { fill: var(--muted); font-size: 18px; font-weight: 500; }
.policy-state-leader { fill: none; stroke: var(--context); stroke-width: 2; stroke-dasharray: 4 4; }
.policy-state-annotation circle { fill: var(--context); }
.residual-curve { fill: none; stroke: var(--residual); stroke-width: 3; }
.residual-curve.is-current { stroke-width: 6; }
#residual-head polygon { fill: var(--residual); }
.arm-label { font-size: 13px; font-weight: 800; }
.arm-label--base { fill: var(--gold-current); opacity: 0.62; }
.arm-label--refined { fill: var(--asrr); }
.illustration-note { padding: 4px 0; color: var(--muted); font-size: 0.58rem; font-weight: 700; }
.authored-evidence { display: grid; flex: 1; min-height: 0; grid-template-rows: auto minmax(0, 1fr) auto; gap: 9px; padding-top: 8px; }
.authored-evidence__heading { display: flex; align-items: center; justify-content: space-between; gap: 14px; }
.authored-evidence__heading > div { display: flex; align-items: baseline; gap: 10px; }
.authored-evidence__heading span { color: var(--muted); font-size: 0.6rem; font-weight: 800; text-transform: uppercase; }
.authored-evidence__heading strong { font-size: 0.9rem; }
.phase-badge { padding: 4px 7px; border: 1px solid var(--asrr); border-radius: 4px; color: var(--asrr) !important; }
.authored-media-pair { display: grid; min-height: 0; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
.authored-media-pair figure { display: grid; min-width: 0; min-height: 0; grid-template-rows: minmax(0, 1fr) auto; margin: 0; overflow: hidden; border: 1px solid var(--line); border-radius: 6px; background: #080d13; }
.authored-media-pair video { display: block; width: 100%; height: 100%; min-height: 0; background: #080d13; object-fit: contain; }
.authored-media-pair figcaption { padding: 6px 9px; border-top: 1px solid var(--line); color: var(--muted); font-size: 0.66rem; font-weight: 900; }
.authored-media-pair figure:last-child figcaption { color: var(--asrr); }
.evidence-overlay { display: flex; flex-wrap: wrap; align-items: stretch; gap: 8px; }
.evidence-overlay > div { min-width: 130px; padding: 7px 9px; border-left: 3px solid var(--asrr); background: var(--surface); }
.evidence-overlay strong { display: block; color: var(--asrr); font-size: 0.9rem; }
.evidence-overlay span { color: var(--muted); font-size: 0.58rem; }
.evidence-links { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-left: auto; }
.evidence-links a { display: inline-flex; min-height: 36px; align-items: center; gap: 8px; padding: 7px 10px; border: 1px solid var(--line); border-radius: 5px; background: var(--surface); color: var(--muted); font-size: 0.64rem; font-weight: 800; text-decoration: none; }
.evidence-links a:hover, .evidence-links a:focus-visible { border-color: var(--asrr); color: var(--asrr); }
.evidence-card { display: flex; min-width: 0; flex-direction: column; padding: 0; overflow: hidden; border: 1px solid var(--line); border-radius: 6px; background: var(--surface); text-align: left; }
.evidence-card:hover { border-color: var(--asrr); }
.evidence-card__heading { display: flex; align-items: baseline; justify-content: space-between; gap: 8px; padding: 8px 9px; }
.evidence-card__heading strong { font-size: 0.74rem; }
.evidence-card__heading small { overflow: hidden; color: var(--muted); font-size: 0.58rem; text-overflow: ellipsis; white-space: nowrap; }
.evidence-thumbs { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); min-height: 0; }
.evidence-thumbs > span { position: relative; min-width: 0; background: #0a1018; }
.evidence-thumbs img { width: 100%; height: 100%; min-height: 96px; object-fit: cover; }
.evidence-card.is-featured .evidence-thumbs img { min-height: 240px; }
.evidence-thumbs em { position: absolute; right: 4px; bottom: 4px; padding: 2px 4px; border-radius: 3px; background: rgb(5 10 15 / 0.78); color: #fff; font-size: 0.55rem; font-style: normal; font-weight: 800; }
.evidence-card__action { padding: 7px 9px; color: var(--asrr); font-size: 0.62rem; font-weight: 800; }
.evidence-label--recorded { color: var(--asrr); }
.is-inactive { opacity: 0.42; }

.inspector { display: flex; flex-direction: column; padding: 18px; overflow: auto; }
.inspector__header { display: flex; align-items: start; justify-content: space-between; gap: 12px; }
.chapter-index { color: var(--base); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.72rem; font-weight: 800; }
.inspector__takeaway { margin-top: 9px; color: var(--muted); font-size: 0.82rem; }
.operation-list { display: grid; gap: 8px; margin: 12px 0; }
.operation-list div { display: grid; grid-template-columns: 62px minmax(0, 1fr); gap: 8px; }
.operation-list dt { color: var(--muted); font-size: 0.72rem; font-weight: 800; text-transform: uppercase; }
.operation-list dd { margin: 0; font-size: 0.8rem; }
.operation-list code { color: var(--residual); }
.inspector__formula { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 7px; padding: 10px 8px; border: 1px solid var(--line); border-radius: 6px; background: var(--surface-soft); font-family: ui-serif, Georgia, serif; font-size: 0.93rem; }
.formula-residual { color: var(--residual); }
.segmented-control { display: grid; grid-template-columns: repeat(2, 1fr); margin-top: auto; padding-top: 12px; }
.segmented-control button { min-height: 38px; border: 1px solid var(--line); background: var(--surface-soft); font-size: 0.77rem; font-weight: 800; }
.segmented-control button:first-child { border-radius: 5px 0 0 5px; }
.segmented-control button:last-child { margin-left: -1px; border-radius: 0 5px 5px 0; }
.segmented-control button[aria-pressed="true"] { position: relative; border-color: var(--context); background: color-mix(in srgb, var(--context) 16%, var(--surface)); color: var(--text); }
.hold-command, .retry-command { display: inline-flex; min-height: 40px; align-items: center; justify-content: center; gap: 8px; margin-top: 10px; padding: 8px 12px; border: 1px solid var(--residual); border-radius: 5px; background: transparent; color: var(--residual); font-size: 0.78rem; font-weight: 800; }

.playback { display: grid; min-height: 76px; grid-template-columns: auto minmax(180px, 1fr) auto; align-items: center; gap: 18px; padding: 12px 18px; border-top: 1px solid var(--line); background: var(--surface); }
.playback__commands { display: flex; align-items: center; gap: 7px; }
.icon-command, .play-command { display: inline-flex; min-width: 40px; min-height: 40px; align-items: center; justify-content: center; gap: 7px; padding: 7px 10px; border: 1px solid var(--line); border-radius: 5px; background: var(--surface-soft); }
.play-command { min-width: 88px; border-color: var(--asrr); background: var(--asrr); color: #081713; font-size: 0.8rem; font-weight: 900; }
.timeline-wrap { position: relative; display: flex; min-width: 0; align-items: center; }
#tour-timeline { width: 100%; accent-color: var(--asrr); }
.timeline-chapters { position: absolute; right: 8px; left: 8px; height: 12px; pointer-events: none; }
.timeline-chapters i { position: absolute; width: 1px; height: 12px; background: var(--line); }
.elapsed-time { color: var(--muted); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.74rem; white-space: nowrap; }

.media-dialog { width: min(1080px, calc(100% - 36px)); max-height: calc(100dvh - 36px); padding: 0; overflow: auto; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); color: var(--text); box-shadow: 0 28px 70px rgb(0 0 0 / 0.5); }
.media-dialog::backdrop { background: rgb(2 7 13 / 0.78); }
.dialog-heading { display: flex; align-items: center; justify-content: space-between; gap: 18px; padding: 16px 18px; border-bottom: 1px solid var(--line); }
.media-pair { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; padding: 16px; }
.media-pair figure { min-width: 0; margin: 0; overflow: hidden; border: 1px solid var(--line); border-radius: 6px; background: var(--surface-soft); }
.media-pair video { display: block; width: 100%; aspect-ratio: 16 / 9; background: #080d13; object-fit: contain; }
.media-pair figcaption { padding: 8px 10px; border-top: 1px solid var(--line); color: var(--muted); font-size: 0.72rem; font-weight: 800; }
.media-status { padding: 0 16px 16px; color: var(--muted); font-size: 0.84rem; }
.retry-command { margin: 0 16px 16px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

@media (max-width: 820px) {
  .explainer-app { height: auto; min-height: 100dvh; grid-template-rows: auto auto auto auto; overflow: visible; }
  .app-header { grid-template-columns: 1fr auto; }
  .app-title { grid-row: 2; grid-column: 1 / -1; justify-content: flex-start; }
  .chapter-tabs { overflow-x: auto; grid-template-columns: repeat(4, minmax(150px, 1fr)); }
  .workbench { grid-template-columns: minmax(0, 1fr); }
  .stage-viewport { min-height: 390px; }
  .scene { height: auto; min-width: 0; min-height: 100%; overflow: visible; }
  .diagram-wrap, .refinement-diagram { height: auto; min-height: 300px; }
  .diagram-wrap > .trajectory-svg { position: static; min-height: 300px; }
  .refinement-diagram { flex: none; grid-template-rows: minmax(260px, 1fr) auto; }
  .inspector { overflow: visible; }
  .segmented-control { margin-top: 0; }
  .playback { position: sticky; bottom: 0; z-index: 5; grid-template-columns: 1fr auto; }
  .playback__commands { grid-column: 1; }
  .timeline-wrap { grid-row: 2; grid-column: 1 / -1; }
  .elapsed-time { grid-column: 2; grid-row: 1; }
  .evidence-wall.is-expanded { grid-template-columns: repeat(2, minmax(190px, 1fr)); }
  .adaptation-compare { grid-template-columns: minmax(0, 1fr); overflow: visible; }
  .lane-trajectory .interface-arm { flex: none; height: auto; aspect-ratio: 9 / 5; }
  .trajectory-svg .action-point text { font-size: 23px; }
  .residual-mode-row { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 600px) {
  .chapter-tabs { overflow: visible; grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 480px) {
  .app-header { padding: 10px 14px; }
  .app-title span { display: none; }
  .workbench { gap: 10px; padding: 10px; }
  .panel-heading { min-height: 78px; padding: 12px; }
  .stage-viewport { min-height: 330px; }
  .inspector { padding: 15px; }
  .playback { gap: 9px; padding: 10px; }
  .play-command { min-width: 76px; }
  .media-pair { grid-template-columns: 1fr; }
  .metric-ribbon { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .lane-flow { grid-template-columns: minmax(90px, 1fr) auto minmax(100px, 1fr) auto minmax(80px, 1fr); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}

/* Clean, fixed-format presentation for video capture. */
[data-export] { cursor: none; }
[data-export] .explainer-app { grid-template-rows: minmax(0, 1fr); }
[data-export] .app-header,
[data-export] .chapter-tabs,
[data-export] .playback,
[data-export] .segmented-control,
[data-export] .hold-command,
[data-export] .recorded-evidence-chip,
[data-export] .evidence-links { display: none; }
[data-export] .workbench { grid-template-columns: minmax(0, 1fr) 440px; gap: 24px; padding: 32px; }
[data-export] .panel-heading { min-height: 100px; padding: 22px 26px; }
[data-export] .panel-heading h1 { font-size: 28px; }
[data-export] .overline, [data-export] .scene-meta { font-size: 13px; }
[data-export] .scene { padding: 20px 26px; }
[data-export] .inspector { justify-content: center; padding: 28px; overflow: hidden; }
[data-export] .inspector h2 { margin-top: 20px; font-size: 28px; }
[data-export] .inspector__takeaway { margin-top: 20px; font-size: 21px; }
[data-export] .operation-list { gap: 20px; margin: 28px 0; }
[data-export] .operation-list div { grid-template-columns: 78px minmax(0, 1fr); }
[data-export] .operation-list dt { font-size: 14px; }
[data-export] .operation-list dd { font-size: 18px; }
[data-export] .inspector__formula { font-size: 21px; }
[data-export] .trajectory-legend { margin: 18px 0 8px; font-size: 15px; }
[data-export] .lane-trajectory .trajectory-legend { font-size: 13px; }
[data-export] .lane-heading { padding: 16px; }
[data-export] .lane-heading span { font-size: 13px; }
[data-export] .lane-heading strong { font-size: 21px; }
[data-export] .mini-block { min-height: 64px; font-size: 14px; }
[data-export] .mini-block small { font-size: 12px; }
[data-export] .mode-pill strong { font-size: 19px; }
[data-export] .mode-pill span, [data-export] .policy-data span, [data-export] .refiner-node span,
[data-export] .method-status span, [data-export] .illustration-note { font-size: 12px; }
[data-export] .policy-data strong { font-size: 15px; }
[data-export] .authored-evidence__heading strong { font-size: 24px; }
[data-export] .authored-evidence__heading span { font-size: 14px; }
[data-export] .authored-media-pair figcaption { padding: 12px; font-size: 18px; }
[data-export] .evidence-overlay > div { min-width: 200px; padding: 12px 16px; }
[data-export] .evidence-overlay strong { font-size: 24px; }
[data-export] .evidence-overlay span { font-size: 15px; }