:root {
  --max-width: 1100px;
  --accent: #2563eb;
  --accent-red: #dc2626;
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --fg: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 14px rgba(15, 23, 42, 0.06);
  --radius: 10px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: "Inter", -apple-system, "Segoe UI", "Helvetica Neue", system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ─────────────── Sticky TOC ─────────────── */
.toc-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.toc-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.7rem 1.25rem;
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  flex-wrap: wrap;
  font-size: 0.86rem;
}
.toc-inner a {
  color: var(--muted);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.15s ease;
  white-space: nowrap;
}
.toc-inner a:hover { color: var(--accent); }

/* ─────────────── Hero ─────────────── */
.page-header {
  max-width: var(--max-width);
  margin: 4.5rem auto 3rem;
  padding: 0 1.25rem;
  text-align: center;
}
.title {
  font-family: "Inter", -apple-system, "Segoe UI", "Helvetica Neue", system-ui, sans-serif;
  font-size: clamp(1.55rem, 3vw, 2.55rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  margin: 0 auto;
  line-height: 1.22;
  color: var(--fg);
  max-width: 900px;
  text-wrap: balance;
}
.title-name {
  color: var(--accent-red);
  font-weight: 800;
  letter-spacing: 0.005em;
}
.title-colon {
  color: var(--fg);
  font-weight: 700;
  margin-right: 0.15em;
}
.title-expand {
  display: inline;
  font-weight: 500;
  color: var(--fg);
}
.acc {
  color: var(--accent-red);
  font-weight: 700;
}

.hero-authors {
  margin-top: 1.4rem;
  font-family: "Inter", -apple-system, "Segoe UI", sans-serif;
}
.author-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.3rem 1.6rem;
  font-size: 1.05rem;
  color: var(--fg);
}
.author-name { font-weight: 500; }
.author-name sup {
  color: var(--muted);
  font-weight: 400;
  margin-left: 0.05em;
  font-size: 0.75em;
}
.author-affil {
  margin-top: 0.5rem;
  font-size: 0.85rem;
  color: var(--muted);
}
.author-affil sup { margin-right: 0.1em; }

/* ─────────────── Buttons ─────────────── */
.link-row {
  margin-top: 2.25rem;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.65rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55em;
  padding: 0.65rem 1.25rem;
  background: var(--fg);
  color: var(--bg);
  border: 1.5px solid var(--fg);
  border-radius: 999px;
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
  font-family: inherit;
}
.btn:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn-ghost {
  background: transparent;
  color: var(--fg);
}
.btn-ghost:hover {
  background: var(--fg);
  color: var(--bg);
  border-color: var(--fg);
}
.btn-logo {
  height: 1.05em;
  width: auto;
  filter: brightness(0) invert(1);
  transition: filter 0.15s ease;
}
.btn-ghost .btn-logo { filter: brightness(0); }
.btn-ghost:hover .btn-logo { filter: brightness(0) invert(1); }

/* ─────────────── Sections ─────────────── */
.section {
  max-width: var(--max-width);
  margin: 5rem auto;
  padding: 0 1.25rem;
  scroll-margin-top: 5rem;
}
.section--no-heading { margin-top: 2.5rem; }
.section h2 {
  font-family: "Newsreader", Georgia, serif;
  font-size: clamp(1.6rem, 3vw, 2.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 1.5rem;
  padding-left: 0.9rem;
  position: relative;
  color: var(--fg);
}
.section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35em;
  bottom: 0.35em;
  width: 4px;
  background: var(--accent);
  border-radius: 2px;
}
.section h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 2.25rem 0 0.75rem;
  color: var(--fg);
  letter-spacing: -0.01em;
}
.section p { color: var(--fg); text-align: justify; text-justify: inter-word; }
/* Captions stay centered even though they are <p> inside a section. */
.section p.teaser-caption { text-align: center; }

.grid { display: grid; gap: 0.85rem; }

video {
  width: 100%;
  height: auto;
  display: block;
  background: #000;
  border-radius: 6px;
}

.caption {
  font-size: 0.85rem;
  color: var(--muted);
  text-align: center;
  margin: 0.4rem 0;
  line-height: 1.45;
}

/* ─────────────── Video container / labels ─────────────── */
.video-container {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  background: #000;
  box-shadow: var(--shadow-md);
}
.video-container video { display: block; width: 100%; height: auto; }

/* Labels are placed in a 3-column grid overlay so each label centers
   on its panel regardless of video display width. */
.video-label-row {
  position: absolute;
  top: 10px;
  left: 0;
  right: 0;
  display: grid;
  pointer-events: none;
  z-index: 4;
  padding: 0 6px;
}
.video-label {
  justify-self: center;
  background: rgba(15, 23, 42, 0.7);
  color: #fff;
  padding: 4px 11px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  white-space: nowrap;
  backdrop-filter: blur(6px);
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
}
.video-label.is-ours {
  background: rgba(37, 99, 235, 0.9);
}

/* ─────────────── Teaser 2×4 grid ─────────────── */
.teaser-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.65rem;
  max-width: var(--max-width);
  margin: 0 auto;
}
.teaser-tile {
  position: relative;
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: #000;
  box-shadow: var(--shadow-md);
  aspect-ratio: 4 / 3;
}
.teaser-tile-crop {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
}
.teaser-tile-crop video {
  display: block;
  height: 100%;
  /* width is set inline (scale factor × 100%) so the left "Ours" panel of
     the comparison strip fills the tile and the rest is clipped.
     `object-position: left center` keeps the leftmost panel and balances
     vertical crop for cases whose panel aspect (e.g. AgiBot 1:1) differs
     from the 4:3 tile. */
  object-fit: cover;
  object-position: left center;
  background: #000;
  border-radius: 0;
}
.teaser-tile-label {
  position: absolute;
  left: 10px;
  bottom: 10px;
  background: rgba(15, 23, 42, 0.72);
  color: #fff;
  padding: 4px 11px;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  backdrop-filter: blur(6px);
  max-width: calc(100% - 20px);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.teaser-caption {
  text-align: center;
  font-size: 0.92rem;
  color: var(--muted);
  margin: 1rem auto 1.5rem;
  max-width: 720px;
  line-height: 1.55;
}
.teaser-caption strong { color: var(--fg); font-weight: 600; }

/* Key-takeaway pills under teaser */
.teaser-pills {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
  max-width: var(--max-width);
  margin: 0 auto;
}
.teaser-pill {
  padding: 0.95rem 1.1rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-align: left;
}
.teaser-pill-stat {
  font-family: "Newsreader", Georgia, serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: -0.01em;
  margin-bottom: 0.2rem;
  line-height: 1.2;
}
.teaser-pill-body {
  font-size: 0.86rem;
  color: var(--muted);
  line-height: 1.45;
}
@media (max-width: 900px) {
  .teaser-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 720px) {
  .teaser-pills { grid-template-columns: 1fr; }
  .teaser-tile-label { font-size: 0.65rem; padding: 3px 8px; left: 6px; bottom: 6px; }
}

/* ─────────────── Dataset release cards ─────────────── */
.data-release {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin: 1.75rem 0 2.5rem;
}
.dataset-card {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.15rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-soft);
  text-decoration: none;
  color: inherit;
  transition: transform 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}
.dataset-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.12);
}
.dataset-card .hf-logo {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
}
.dataset-meta { flex: 1; min-width: 0; }
.dataset-name {
  font-weight: 600;
  font-size: 0.98rem;
  color: var(--fg);
  margin-bottom: 0.2rem;
  letter-spacing: -0.005em;
}
.dataset-kind {
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.4;
}
.dataset-cta {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent);
  white-space: nowrap;
  flex-shrink: 0;
}
@media (max-width: 720px) {
  .data-release { grid-template-columns: 1fr; }
}

/* ─────────────── Data donuts ─────────────── */
.data-donuts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-top: 2rem;
  align-items: start;
}
.data-donut {
  margin: 0;
  text-align: center;
}
.data-donut figcaption {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.85rem;
}
.donut-wrap {
  position: relative;
  max-width: 300px;
  margin: 0 auto;
}
.donut {
  width: 100%;
  display: block;
}
.donut-center {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  text-align: center;
}
.donut-total {
  font-family: "Newsreader", Georgia, serif;
  font-size: 2.1rem;
  font-weight: 700;
  color: var(--fg);
  letter-spacing: -0.025em;
  line-height: 1;
}
.donut-unit {
  font-size: 0.78rem;
  color: var(--muted);
  margin-top: 0.15rem;
  letter-spacing: 0.04em;
}
.donut-sub {
  font-size: 0.72rem;
  color: var(--muted);
  margin-top: 0.45rem;
  letter-spacing: 0.04em;
}
.donut-legend {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 0.6rem 1.5rem;
  margin-top: 2rem;
  padding: 1.25rem 1.5rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.legend-item {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  font-size: 0.85rem;
  line-height: 1.4;
}
.swatch {
  width: 12px;
  height: 12px;
  border-radius: 3px;
  flex-shrink: 0;
  margin-top: 0.3rem;
}
.legend-text { flex: 1; min-width: 0; }
.legend-name {
  font-weight: 600;
  color: var(--fg);
}
.legend-kind {
  font-weight: 400;
  color: var(--muted);
  margin-left: 0.4em;
  font-size: 0.78rem;
}
.legend-vals {
  color: var(--muted);
  font-variant-numeric: tabular-nums;
  font-size: 0.8rem;
  margin-top: 0.1rem;
}
.vals-arrow { margin: 0 0.4em; opacity: 0.6; }
.vals-to { color: var(--fg); font-weight: 500; }

/* ─────────────── BibTeX ─────────────── */
#bibtex-content {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  padding: 1.1rem 1.25rem;
  border-radius: var(--radius);
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.55;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  color: var(--fg);
  margin-bottom: 1rem;
}

/* ─────────────── Results groups ─────────────── */
.results-group {
  margin: 3rem 0;
  padding: 1.5rem 1.5rem 1.75rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.results-group:first-child { margin-top: 1.5rem; }
.group-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 0.85rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}
.group-header h3 {
  margin: 0;
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--fg);
  letter-spacing: -0.01em;
}
.case-count {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  background: var(--bg);
  padding: 0.25rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  white-space: nowrap;
}
.results-cases {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}
.results-case { margin: 0; }
.results-case .caption { margin-bottom: 0.5rem; text-align: left; font-weight: 500; color: var(--fg); }

/* ─────────────── Baselines grid ─────────────── */
.baselines-case { margin: 2.5rem 0; }
.baselines-title {
  text-align: left;
  font-weight: 600;
  color: var(--fg);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}
.baselines-grid {
  display: grid;
  gap: 0.85rem;
  grid-template-columns: repeat(4, 1fr);
}
.baseline-cell {
  position: relative;
}
.baseline-cell video {
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: #000;
  border-radius: 6px;
}
.baseline-cell.is-ours {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 8px;
}
.baseline-cell .caption {
  text-align: center;
  font-weight: 500;
  color: var(--fg);
}
.baseline-cell.is-ours .caption {
  color: var(--accent);
  font-weight: 600;
}
@media (max-width: 1100px) {
  .baselines-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
  .baselines-grid { grid-template-columns: 1fr; }
}

/* ─────────────── Ablation blocks ─────────────── */
.ablation-block { margin: 2.5rem 0; }
.ablation-block + .ablation-block {
  margin-top: 4rem;
  padding-top: 3rem;
  border-top: 1px solid var(--border);
}
.ablation-q {
  font-family: "Newsreader", Georgia, serif;
  font-size: clamp(1.35rem, 2.2vw, 1.75rem);
  font-weight: 700;
  color: var(--fg);
  letter-spacing: -0.01em;
  margin: 0 0 0.85rem;
  text-wrap: balance;
}
.ablation-a {
  font-size: 1.025rem;
  line-height: 1.65;
  color: var(--fg);
  margin: 0 0 1.5rem;
}
.ablation-a strong { color: var(--accent); }

/* Inline math (variable names with subscripts in method caption) */
.math {
  font-family: "Newsreader", Georgia, serif;
  font-style: italic;
  font-weight: 500;
}
.math sub { font-style: normal; font-size: 0.78em; }

/* Highlight Ours/Skeleton labels inside ablation grids */
.caption.is-ours { color: var(--accent); font-weight: 600; }

/* ─────────────── Tooltips (hover bubble on labels) ─────────────── */
[data-tooltip] {
  position: relative;
  cursor: help;
  border-bottom: 1px dotted var(--muted);
}
[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  left: 50%;
  bottom: calc(100% + 8px);
  transform: translateX(-50%) translateY(4px);
  background: rgba(15, 23, 42, 0.96);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: 0;
  padding: 0.55rem 0.75rem;
  border-radius: 6px;
  white-space: normal;
  width: max-content;
  max-width: 260px;
  text-align: left;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s ease, transform 0.15s ease;
  z-index: 50;
  box-shadow: 0 6px 20px rgba(15, 23, 42, 0.25);
}
[data-tooltip]:hover::after,
[data-tooltip]:focus-visible::after {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ─────────────── Footer ─────────────── */
.page-footer {
  max-width: var(--max-width);
  margin: 6rem auto 3rem;
  padding: 2.5rem 1.25rem 0;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--muted);
}
.footer-authors { margin-bottom: 1.5rem; }
.footer-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.4rem 1.5rem;
  font-size: 1rem;
  color: var(--fg);
}
.footer-name { font-weight: 500; }
.footer-name sup { color: var(--muted); font-weight: 400; margin-left: 0.1em; }
.footer-affil {
  margin-top: 0.5rem;
  font-size: 0.82rem;
  color: var(--muted);
  font-style: italic;
}
.footer-affil sup { font-style: normal; }
.page-footer p { margin: 0.35rem 0; }
.footer-meta { font-size: 0.82rem; }
.footer-sub { font-size: 0.74rem; opacity: 0.75; margin-top: 0.75rem; }
.footer-meta time { font-variant-numeric: tabular-nums; }

/* ─────────────── Scroll reveal ─────────────── */
.reveal {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.55s ease, transform 0.55s ease;
  will-change: opacity, transform;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ─────────────── Responsive ─────────────── */
@media (max-width: 768px) {
  body { font-size: 16px; }
  .grid { grid-template-columns: 1fr; }
  .page-header { margin: 4rem auto 2.5rem; }
  .link-row { gap: 0.5rem; }
  .btn { padding: 0.55rem 1rem; font-size: 0.9rem; }
  .section { margin: 3.5rem auto; }
  .toc-inner {
    flex-wrap: nowrap;
    justify-content: flex-start;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    gap: 1.1rem;
    padding: 0.6rem 1rem;
  }
  .toc-inner::-webkit-scrollbar { display: none; }
  .data-donuts { grid-template-columns: 1fr; }
  .video-label { font-size: 0.65rem; padding: 3px 7px; }
  .video-label-row { top: 6px; padding: 0 4px; }
  .results-group { padding: 1.1rem 1rem 1.25rem; }
  .group-header { flex-wrap: wrap; }
  .footer-row { font-size: 0.92rem; gap: 0.3rem 1rem; }
}

/* Single-video teaser (replaces the 2x4 tile grid). */
.teaser-grand {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto 1.5rem;
  border-radius: 12px;
  overflow: hidden;
  background: #000;
}
.teaser-grand video {
  width: 100%;
  height: auto;
  display: block;
}

/* Narrated overview video below the abstract. */
.overview-video {
  margin: 1.5rem auto 0;
  max-width: 1280px;
}
.overview-video video {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 12px;
  background: #000;
}

/* Dataset sample grids (Data section: 8 cards, each 2x2 video tiles). */
.dataset-grids {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
  margin: 1.5rem 0;
}
@media (max-width: 760px) {
  .dataset-grids { grid-template-columns: 1fr; }
}
.dataset-grid-card {
  background: #f5f5f5;
  border-radius: 12px;
  padding: 0.75rem 0.9rem 1rem;
}
.dataset-grid-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.6rem;
  font-size: 0.9rem;
  color: #333;
}
.dataset-grid-label { font-weight: 600; }
.dataset-grid-meta  { color: #666; }
.dataset-grid-2x2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
  background: #000;
  border-radius: 8px;
  overflow: hidden;
}
.dataset-grid-2x2 video {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
  background: #000;
}

/* ─────────────── Tabs (shared) ─────────────── */
.tabs-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border);
}
.tab-btn {
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.005em;
  color: var(--muted);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.45rem 1.05rem;
  cursor: pointer;
  white-space: nowrap;
  transition: color 0.15s ease, background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}
.tab-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
}
.tab-btn.is-active {
  color: #fff;
  background: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.22);
}
.tab-btn .tab-sub {
  font-weight: 400;
  opacity: 0.7;
  margin-left: 0.4em;
  font-size: 0.92em;
}
.tabs-body { min-height: 1px; }
@media (max-width: 768px) {
  .tabs-nav {
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .tabs-nav::-webkit-scrollbar { display: none; }
}

/* ─────────────── Data statistics table ─────────────── */
.data-stats {
  margin: 1.75rem 0 2rem;
  overflow-x: auto;
}
.data-stats table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  font-variant-numeric: tabular-nums;
}
.data-stats caption {
  caption-side: top;
  text-align: left;
  font-size: 0.82rem;
  color: var(--muted);
  margin-bottom: 0.7rem;
  line-height: 1.5;
}
.data-stats th,
.data-stats td {
  padding: 0.5rem 0.85rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.data-stats th.num,
.data-stats td.num { text-align: right; }
.data-stats thead th {
  font-weight: 600;
  color: var(--fg);
  border-bottom: 2px solid var(--border);
}
.data-stats tr.subtotal td {
  font-weight: 600;
  background: var(--bg-soft);
}
.data-stats tr.total td {
  font-weight: 700;
  border-top: 2px solid var(--border);
  background: var(--bg-soft);
}
.data-stats .note {
  font-size: 0.78rem;
  color: var(--muted);
  margin-top: 0.5rem;
}

/* ---- Policy Evaluation ---- */
.pe-intro { max-width: 100%; }
.pe-quant { margin: 1.5rem auto; text-align: center; }
.pe-quant img { max-width: min(820px, 100%); height: auto; border-radius: 8px; }
.pe-quant figcaption { font-size: 0.85rem; color: var(--muted, #666); margin-top: 0.5rem; max-width: 70ch; margin-inline: auto; }

.pe-gridnote { max-width: 100%; color: var(--muted, #666); font-size: 0.92rem; margin-top: 1.5rem; }
.pe-grid { display: flex; flex-direction: column; gap: 2.5rem; margin-top: 1rem; }
.policy-eval-case { margin: 0; }
.pe-head { display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: 0.5rem; margin-bottom: 0.6rem; padding-bottom: 0.5rem; border-bottom: 1px solid var(--border, #e2e2e8); }
.pe-title { display: flex; flex-direction: column; gap: 0.15rem; }
.pe-policy { font-weight: 700; }
.pe-instr { color: var(--muted, #666); font-size: 0.95rem; }
.pe-badges { display: flex; gap: 0.5rem; }
.pe-badge { font-size: 0.8rem; font-weight: 600; padding: 0.15rem 0.55rem; border-radius: 999px; }
.pe-pass { background: #d8f0dc; color: #1a7a32; }
.pe-fail { background: #f6dada; color: #b22222; }

.pe-vids { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 0.6rem; align-items: start; }
.pe-vid { margin: 0; }
.pe-vid video { width: 100%; height: auto; border-radius: 6px; display: block; background: #000; }
.pe-vid figcaption { font-size: 0.78rem; color: var(--muted, #666); margin-top: 0.3rem; text-align: center; }
.pe-error { color: #b22222; }

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

/* ═══════════════ DFD showcase panel ═══════════════ */
.sc-task-nav {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 0.6rem;
}
.sc-task-btn {
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 0.55rem 1.3rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--muted);
  cursor: pointer;
  transition: all 0.15s ease;
}
.sc-task-btn:hover { border-color: var(--accent); color: var(--accent); }
.sc-task-btn.is-active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  box-shadow: var(--shadow-md);
}
.sc-note {
  text-align: center;
  color: var(--muted);
  font-size: 0.88rem;
  margin: 0 0 1rem;
}

/* stage: [prompt+teacher | DFD | DMD] */
.sc-stage {
  display: grid;
  grid-template-columns: 1.1fr 2fr 2fr;
  gap: 12px;
  align-items: stretch;
}
.sc-side {
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-width: 0;
}
.sc-prompt-box {
  flex: 1 1 auto;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.65rem 0.8rem;
  min-height: 70px;
  display: flex;
  flex-direction: column;
}
.sc-prompt-text {
  font-size: 0.78rem;
  line-height: 1.5;
  color: var(--fg);
  overflow-y: auto;
  max-height: 200px;
}
.sc-prompt-box.is-empty .sc-prompt-text::before {
  content: "Conditioned on the input image (first frame shown in each video).";
  color: var(--muted);
  font-style: italic;
}
.sc-box-label {
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  margin-bottom: 0.35rem;
}
.sc-teacher { margin: 0; flex: 0 0 auto; }
.sc-teacher video {
  width: 100%;
  display: block;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #000;
}
.sc-main {
  margin: 0;
  position: relative;
  min-width: 0;
}
.sc-main video {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #000;
}
.sc-vid-label {
  position: absolute;
  top: 10px;
  left: 10px;
  z-index: 2;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.72);
  color: #fff;
  backdrop-filter: blur(4px);
}
.sc-vid-label.is-ours { background: var(--accent); }

/* filmstrip */
.sc-strip {
  display: flex;
  gap: 8px;
  margin-top: 12px;
  overflow-x: auto;
  padding-bottom: 6px;
  scrollbar-width: thin;
}
.sc-thumb {
  flex: 0 0 auto;
  width: 108px;
  padding: 0;
  border: 2px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  cursor: pointer;
  background: var(--bg);
  transition: border-color 0.15s ease, transform 0.15s ease;
  display: flex;
  flex-direction: column;
}
.sc-thumb:hover { border-color: var(--accent); transform: translateY(-2px); }
.sc-thumb.is-active { border-color: var(--accent); box-shadow: var(--shadow-md); }
.sc-thumb img { width: 100%; display: block; aspect-ratio: 16 / 9; object-fit: cover; }
.sc-thumb span {
  font-size: 0.62rem;
  font-weight: 600;
  color: var(--muted);
  padding: 3px 4px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sc-thumb.is-active span { color: var(--accent); }
.sc-error { color: var(--accent-red); text-align: center; }

@media (max-width: 800px) {
  .sc-stage { grid-template-columns: 1fr 1fr; }
  .sc-side { grid-column: 1 / -1; flex-direction: row; }
  .sc-prompt-box { flex: 1.4; }
  .sc-teacher { flex: 1; }
  .sc-prompt-text { max-height: 110px; }
}

/* ═══════════════ Method code block ═══════════════ */
.method-code {
  background: #0f172a;
  color: #e2e8f0;
  border-radius: var(--radius);
  padding: 0.9rem 1.1rem;
  font-size: 0.82rem;
  line-height: 1.6;
  overflow-x: auto;
}
.method-code code { font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace; }
.method-note { color: var(--muted); font-size: 0.95rem; }

/* ═══════════════ Quantitative table ═══════════════ */
.table-scroll { overflow-x: auto; }
.quant-table {
  border-collapse: collapse;
  font-size: 0.78rem;
  min-width: 880px;
  width: 100%;
}
.quant-table th, .quant-table td {
  padding: 0.45rem 0.55rem;
  text-align: center;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
.quant-table td:first-child, .quant-table .qt-cols th:first-child { text-align: left; font-weight: 600; }
.quant-table .qt-groups th {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--muted);
  border-bottom: 2px solid var(--border);
}
.quant-table .qt-cols th {
  font-weight: 600;
  font-size: 0.72rem;
  color: var(--muted);
  line-height: 1.3;
}
.quant-table .qt-teacher td { color: var(--muted); border-bottom: 2px solid var(--border); }
.quant-table .qt-ours td { background: rgba(37, 99, 235, 0.06); }
.quant-table .qt-ours td:first-child { color: var(--accent); }

/* ═══════════════ DFD page overrides ═══════════════ */
/* 1. breathing room between Paper/Code buttons and the takeaway pills */
.page-header .teaser-pills { margin-top: 3.25rem; }

/* 2. Qualitative-results sections span the full page width */
.section-showcase {
  max-width: none;
  padding-left: clamp(1.25rem, 3vw, 3.5rem);
  padding-right: clamp(1.25rem, 3vw, 3.5rem);
}
.section-showcase .sc-stage { min-height: 46vh; }
/* tighter rhythm between the three back-to-back showcase sections */
.section-showcase + .section-showcase { margin-top: 3.5rem; }

/* quant table subsection headings */
.quant-sub {
  font-family: "Newsreader", Georgia, serif;
  font-size: 1.25rem;
  font-weight: 700;
  margin: 2.4rem 0 0.4rem;
}
.quant-sub:first-of-type { margin-top: 1.6rem; }
.quant-caption { color: var(--muted); font-size: 0.92rem; margin: 0.2rem 0 0.8rem; }

/* ═══════════════ Method: equation + algorithm ═══════════════ */
.method-sub {
  font-family: "Newsreader", Georgia, serif;
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2.6rem 0 0.6rem;
}
.method-eq {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.1rem 1rem;
  margin: 1rem 0 1.2rem;
  overflow-x: auto;
  text-align: center;
  font-size: 1.02rem;
}
.algo-box { margin: 1.4rem 0; }
.algo-title {
  font-weight: 600;
  font-size: 0.92rem;
  border-top: 2px solid var(--fg);
  border-bottom: 1px solid var(--border);
  padding: 0.5rem 0.2rem;
  margin-bottom: 0;
}
.algo-box .method-code {
  margin-top: 0;
  border-radius: 0 0 var(--radius) var(--radius);
}
.code-line { display: block; min-height: 1.3em; }
.code-hl {
  background: rgba(170, 0, 255, 0.22);
  border-left: 3px solid #c084fc;
  margin-left: -1.1rem;
  padding-left: calc(1.1rem - 3px);
  color: #e9d5ff;
  font-weight: 700;
}
.algo-note {
  font-size: 0.86rem;
  color: var(--muted);
  margin-top: 0.5rem;
}
.hl-word {
  background: rgba(170, 0, 255, 0.14);
  color: #7c3aed;
  font-weight: 700;
  padding: 0 4px;
  border-radius: 4px;
}

/* ═══════════════ Ablation video grids ═══════════════ */
.ab-block { margin: 2.4rem 0; }
.ab-block:first-of-type { margin-top: 1.4rem; }
.ab-title {
  font-family: "Newsreader", Georgia, serif;
  font-size: 1.35rem;
  font-weight: 700;
  margin: 0 0 0.4rem;
}
.ab-desc { color: var(--muted); font-size: 0.95rem; margin: 0 0 1rem; max-width: 80ch; }

.ab-grid {
  display: grid;
  gap: 10px;
  align-items: center;
}
.ab-col-head {
  font-size: 0.85rem;
  font-weight: 700;
  text-align: center;
  padding: 0.4rem 0.5rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--fg);
}
.ab-col-head.is-ours {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.ab-rowlabel-spacer { }
.ab-row-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--muted);
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  text-align: center;
  justify-self: center;
  white-space: nowrap;
}
.ab-cell { margin: 0; }
.ab-cell video {
  width: 100%;
  display: block;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #000;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}
@media (max-width: 640px) {
  .ab-row-label { writing-mode: horizontal-tb; transform: none; }
}

/* ═══════════════ DFD title: stable two-line layout ═══════════════ */
.title-line { display: block; }
.title-sub {
  font-weight: 500;
  font-size: clamp(0.78rem, 1.95vw, 1.2rem);
  white-space: nowrap;          /* keep the subtitle on a single line */
  margin-top: 0.45rem;
  color: var(--fg);
}
.title-acc { color: var(--accent-red); font-weight: 800; }

/* ═══════════════ Jupyter-notebook code cell ═══════════════ */
.nb-cell {
  margin: 1.3rem 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  max-width: 880px;
}
.nb-head {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.45rem 0.8rem;
  background: #f3f4f6;
  border-bottom: 1px solid var(--border);
}
.nb-dots { display: inline-flex; gap: 5px; }
.nb-dots i {
  width: 11px; height: 11px; border-radius: 50%; display: inline-block;
}
.nb-dots i:nth-child(1) { background: #ff5f56; }
.nb-dots i:nth-child(2) { background: #ffbd2e; }
.nb-dots i:nth-child(3) { background: #27c93f; }
.nb-title {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.78rem;
  color: var(--muted);
}
.nb-body {
  display: flex;
  align-items: flex-start;
  background: #fbfbfd;
}
.nb-prompt {
  flex: 0 0 auto;
  padding: 0.8rem 0.5rem 0.8rem 0.8rem;
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.78rem;
  color: #9333ea;
  user-select: none;
}
.nb-code {
  margin: 0;
  padding: 0.8rem 1rem 0.8rem 0.4rem;
  overflow-x: auto;
  font-size: 0.8rem;
  line-height: 1.55;
  flex: 1 1 auto;
}
.nb-code code { font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace; }
.nb-line { display: block; min-height: 1.2em; }
.nb-hl {
  background: rgba(37, 99, 235, 0.10);
  border-left: 3px solid var(--accent);
  margin-left: -1rem;
  padding-left: calc(1rem - 3px);
}
/* token colors (jupyter-ish) */
.tok-com { color: #16a34a; font-style: italic; }
.tok-kw  { color: #9333ea; font-weight: 600; }
.tok-fn  { color: #2563eb; }
.tok-num { color: #c2410c; }

/* ═══════════════ Limitation video grid ═══════════════ */
.limit-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  max-width: 1100px;
  margin: 0 auto;
}
.limit-grid video {
  width: 100%;
  display: block;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #000;
}
@media (max-width: 600px) { .limit-grid { grid-template-columns: 1fr; } }

/* ═══════════════ TL;DR line ═══════════════ */
.tldr {
  max-width: 760px;
  margin: 2.2rem auto 0;
  padding: 0.9rem 1.2rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 10px;
  font-size: 1.0rem;
  line-height: 1.6;
  color: var(--fg);
  text-align: left;
}
.tldr-tag {
  font-weight: 800;
  color: var(--accent);
  letter-spacing: 0.04em;
  margin-right: 0.5rem;
}

/* ═══════════════ Diversity grid (2 × 8) ═══════════════ */
.dv-intro { color: var(--muted); margin: 0 0 1rem; }
.dv-headers {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 8px;
}
.dv-head {
  text-align: center;
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0.4rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
}
.dv-head.is-ours { background: var(--accent); border-color: var(--accent); color: #fff; }
.dv-grid {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 6px;
}
/* visual divider between the DMD (cols 1-4) and DFD (cols 5-8) halves */
.dv-cell:nth-child(8n+4) { margin-right: 10px; }
.dv-cell video {
  width: 100%;
  display: block;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #000;
}
.dv-cell:nth-child(8n+5) video,
.dv-cell:nth-child(8n+6) video,
.dv-cell:nth-child(8n+7) video,
.dv-cell:nth-child(8n+0) video { border-color: rgba(37,99,235,0.5); }
@media (max-width: 760px) {
  .dv-grid { grid-template-columns: repeat(4, 1fr); }
  .dv-cell:nth-child(8n+4) { margin-right: 0; }
}