/* ---------------------------------------------------------------
   Design tokens (see dataviz skill palette.md for the source values)
--------------------------------------------------------------- */
:root {
  color-scheme: light;
  --surface-1:      #fcfcfb;
  --page-plane:     #f9f9f7;
  --surface-raised: #ffffff;
  --text-primary:   #0b0b0b;
  --text-secondary: #52514e;
  --text-muted:     #898781;
  --gridline:       #e1e0d9;
  --baseline:       #c3c2b7;
  --border:         rgba(11,11,11,0.10);

  --accent:         #196b1a;   /* brand green, darkened from series green for AA text contrast */
  --accent-soft:    #e7f2e4;
  --link:           #1c5cab;

  --series-nosteer: #2a78d6;   /* categorical slot 1 — blue */
  --series-actadd:  #eb6834;   /* categorical slot 6 — orange */
  --series-walqr:   #008300;   /* categorical slot 2 — green (our method) */

  --good-text:      #006300;

  --radius-lg: 16px;
  --radius-md: 10px;
  --radius-sm: 6px;
  --shadow-card: 0 1px 2px rgba(11,11,11,0.06), 0 6px 20px rgba(11,11,11,0.06);
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --surface-1:      #1a1a19;
    --page-plane:     #0d0d0d;
    --surface-raised: #212120;
    --text-primary:   #ffffff;
    --text-secondary: #c3c2b7;
    --text-muted:     #898781;
    --gridline:       #2c2c2a;
    --baseline:       #383835;
    --border:         rgba(255,255,255,0.10);

    --accent:         #4caf50;
    --accent-soft:    #16281a;
    --link:           #6fa8ea;

    --series-nosteer: #3987e5;
    --series-actadd:  #d95926;
    --series-walqr:   #22a83f;

    --good-text:      #0ca30c;

    --shadow-card: 0 1px 2px rgba(0,0,0,0.4), 0 6px 24px rgba(0,0,0,0.35);
  }
}

* { box-sizing: border-box; }
img, video { max-width: 100%; }

html { scroll-behavior: smooth; }

html, body { overflow-x: hidden; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  background: var(--page-plane);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--link); }
a:hover { text-decoration-thickness: 2px; }

.wrap {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 24px;
}

h1, h2, h3 { line-height: 1.25; font-weight: 700; letter-spacing: -0.01em; }
h2 { font-size: clamp(1.4rem, 1.1rem + 1vw, 1.9rem); margin: 0 0 6px; }
h3 { font-size: 1.15rem; margin: 0 0 10px; }
p { margin: 0 0 1em; color: var(--text-primary); }

.section-kicker {
  display: block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 6px;
}

.section-lede {
  color: var(--text-secondary);
  max-width: 66ch;
  margin-bottom: 28px;
}

section {
  padding: 56px 0;
  border-bottom: 1px solid var(--border);
}
section:last-of-type { border-bottom: none; }

/* ---------------------------------------------------------------
   Hero
--------------------------------------------------------------- */
.hero {
  padding: 56px 0 40px;
  background:
    radial-gradient(1200px 400px at 50% -10%, var(--accent-soft), transparent 60%);
  border-bottom: 1px solid var(--border);
}

.hero-logo {
  display: block;
  height: 56px;
  width: auto;
  margin: 0 auto 20px;
}

.hero h1 {
  text-align: center;
  font-size: clamp(1.7rem, 1.2rem + 2vw, 2.5rem);
  max-width: 46ch;
  margin: 0 auto 20px;
}

.authors {
  text-align: center;
  font-size: 1.02rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
}
.authors .star { color: var(--accent); }
.affil {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.pills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 28px;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: 999px;
  background: var(--surface-raised);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-card);
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.92rem;
  text-decoration: none;
  transition: transform 0.12s ease, border-color 0.12s ease;
}
.pill:hover { transform: translateY(-1px); border-color: var(--accent); }
.pill svg { width: 16px; height: 16px; flex: none; fill: currentColor; }
.pill.pill-accent {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.pill.pill-accent:hover { opacity: 0.92; transform: translateY(-1px); }

.version-note {
  max-width: 640px;
  margin: 0 auto;
  padding: 14px 18px;
  border-radius: var(--radius-md);
  background: var(--surface-raised);
  border: 1px solid var(--border);
  font-size: 0.92rem;
  color: var(--text-secondary);
  text-align: center;
}
.version-note b { color: var(--text-primary); }
.version-note a { font-weight: 600; }

/* ---------------------------------------------------------------
   TLDR
--------------------------------------------------------------- */
.tldr {
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  box-shadow: var(--shadow-card);
}
.tldr .section-kicker { margin-bottom: 8px; }
.tldr p { margin: 0; font-size: 1.05rem; }
.tldr p:last-child { margin: 0; }

/* ---------------------------------------------------------------
   Figures
--------------------------------------------------------------- */
figure { margin: 0; min-width: 0; }
figure img, figure video {
  max-width: 100%;
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--surface-raised);
}
figcaption {
  margin-top: 12px;
  font-size: 0.92rem;
  color: var(--text-secondary);
}
figcaption b { color: var(--text-primary); }

.teaser-figure figcaption { text-align: center; max-width: 74ch; margin-left: auto; margin-right: auto; }

.fig-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  align-items: start;
}
.fig-grid > * { min-width: 0; }
@media (max-width: 720px) {
  .fig-grid { grid-template-columns: 1fr; }
}

.fig-grid--equal-h { align-items: stretch; }
.fig-grid--equal-h figure { display: flex; flex-direction: column; }
.fig-img-box {
  height: 260px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--surface-raised);
  overflow: hidden;
}
.fig-img-box img {
  width: auto;
  height: auto;
  max-width: 100%;
  max-height: 100%;
  border: none;
  border-radius: 0;
}

.abstract-card {
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 30px;
  box-shadow: var(--shadow-card);
}
.abstract-card p { color: var(--text-secondary); font-size: 1.02rem; }
.abstract-card p:last-child { margin: 0; }

/* ---------------------------------------------------------------
   Method steps
--------------------------------------------------------------- */
.method-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.method-grid > * { min-width: 0; }
@media (max-width: 720px) {
  .method-grid { grid-template-columns: 1fr; }
}

.method-card {
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-card);
}
.method-card .tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 12px;
}
.method-card.open-loop .tag { background: color-mix(in srgb, var(--series-actadd) 16%, transparent); color: var(--series-actadd); }
.method-card.closed-loop .tag { background: color-mix(in srgb, var(--series-walqr) 16%, transparent); color: var(--series-walqr); }
.method-card p { color: var(--text-secondary); }
.formula {
  display: block;
  font-family: "Cambria Math", "Latin Modern Math", Georgia, serif;
  font-style: italic;
  background: var(--page-plane);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  margin: 12px 0;
  font-size: 0.98rem;
  overflow-x: auto;
  color: var(--text-primary);
}
.method-card ol {
  color: var(--text-secondary);
  padding-left: 1.2em;
  margin: 10px 0 0;
}
.method-card ol li { margin-bottom: 6px; }
.method-card ol li b { color: var(--text-primary); }

/* ---------------------------------------------------------------
   Stat tiles
--------------------------------------------------------------- */
.stat-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 36px;
}
.stat-row > * { min-width: 0; }
@media (max-width: 720px) {
  .stat-row { grid-template-columns: 1fr; }
}
.stat-tile {
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 22px 24px;
  box-shadow: var(--shadow-card);
}
.stat-tile .label {
  font-size: 0.86rem;
  color: var(--text-secondary);
  margin-bottom: 6px;
}
.stat-tile .value {
  font-size: 2.1rem;
  font-weight: 700;
  color: var(--text-primary);
  font-variant-numeric: proportional-nums;
}
.stat-tile .value.good { color: var(--good-text); }
.stat-tile .sub { font-size: 0.84rem; color: var(--text-muted); margin-top: 4px; }

/* ---------------------------------------------------------------
   Bar charts (grouped, per-model small multiples)
--------------------------------------------------------------- */
.chart-panel {
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px 24px 18px;
  box-shadow: var(--shadow-card);
  margin-bottom: 20px;
}
.chart-panel h3 { margin-bottom: 2px; }
.chart-panel .chart-sub { color: var(--text-muted); font-size: 0.85rem; margin-bottom: 18px; }

.legend {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  margin-bottom: 18px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}
.legend-item { display: inline-flex; align-items: center; gap: 6px; }
.legend-swatch { width: 10px; height: 10px; border-radius: 3px; flex: none; }
.legend-swatch.nosteer { background: var(--series-nosteer); }
.legend-swatch.actadd  { background: var(--series-actadd); }
.legend-swatch.walqr   { background: var(--series-walqr); }

.barchart {
  display: flex;
  align-items: flex-end;
  gap: 28px;
  overflow-x: auto;
  padding-bottom: 4px;
  border-bottom: 1px solid var(--gridline);
}
.bar-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  flex: 1 1 0;
  min-width: 195px;
}
.bars {
  display: flex;
  align-items: flex-end;
  gap: 10px;
  height: 150px;
  width: 100%;
  justify-content: center;
}
.bar {
  width: 50px;
  max-width: 60px;
  height: calc(var(--v) * 1%);
  min-height: 2px;
  border-radius: 4px 4px 0 0;
  position: relative;
  display: flex;
  justify-content: center;
}
.bar--nosteer { background: var(--series-nosteer); }
.bar--actadd  { background: var(--series-actadd); }
.bar--walqr   { background: var(--series-walqr); }
.bar-value {
  position: absolute;
  top: -20px;
  font-size: 0.76rem;
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}
.group-label {
  margin-top: 10px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  text-align: center;
  line-height: 1.3;
}

/* ---------------------------------------------------------------
   Video pairs
--------------------------------------------------------------- */
.video-model-block { margin-bottom: 36px; }
.video-model-block:last-child { margin-bottom: 0; }
.video-model-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.video-model-head h3 { margin: 0; }
.model-badge {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 3px 9px;
  border-radius: 999px;
  color: var(--text-muted);
  border: 1px solid var(--border);
}

.video-pairs { display: flex; flex-direction: column; gap: 20px; }
.video-pair-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.video-pair-row > * { min-width: 0; }
@media (max-width: 640px) {
  .video-pair-row { grid-template-columns: 1fr; }
}
.video-pair-row--stacked {
  grid-template-columns: 1fr;
  max-width: 640px;
  margin: 0 auto;
}
.video-card {
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 10px;
  min-width: 0;
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  align-items: center;
}
.video-card video {
  width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
  border: none;
  margin: 0 auto 8px;
  background: #000;
}
.video-card-label, .video-caption { align-self: stretch; }
.video-card-label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.86rem;
  font-weight: 600;
  padding: 0 2px;
}
.status-dot { width: 9px; height: 9px; border-radius: 50%; flex: none; }
.status-dot.fail { background: var(--series-actadd); }
.status-dot.success { background: var(--series-walqr); }
.video-caption { font-size: 0.8rem; color: var(--text-muted); margin: 4px 2px 0; }

/* ---------------------------------------------------------------
   Citation
--------------------------------------------------------------- */
.cite-block {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  overflow-x: auto;
}
.cite-block pre {
  margin: 0;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.82rem;
  color: var(--text-secondary);
  white-space: pre;
}
.copy-btn {
  margin-top: 12px;
  font-size: 0.82rem;
  font-weight: 600;
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface-raised);
  color: var(--text-primary);
  cursor: pointer;
}
.copy-btn:hover { border-color: var(--accent); }

/* ---------------------------------------------------------------
   Footer
--------------------------------------------------------------- */
footer {
  padding: 40px 0 60px;
  text-align: center;
}
footer .logo-row { display: flex; justify-content: center; gap: 24px; margin-bottom: 18px; flex-wrap: wrap; }
footer img.footer-logo { height: 42px; width: auto; opacity: 0.9; }
footer p { color: var(--text-muted); font-size: 0.85rem; margin: 0; }
footer a { color: var(--text-muted); }

/* ---------------------------------------------------------------
   Nav (sticky small links, optional)
--------------------------------------------------------------- */
.skip-link { position: absolute; left: -9999px; }