/* robotdescriptions.com — one stylesheet for the live page (v1) and the two review variants (v2, v3). */

:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --ink: #1d1d1b;
  --muted: #6b6a64;
  --faint: #a3a19a;
  --line: #e6e3dc;
  --accent: #2f5bd3;
  --accent-soft: #e9eefc;
  --code-bg: #f3f1ec;
  --urdf: #2f5bd3;
  --mjcf: #b4502a;
  --sdformat: #2f7d4f;
  --usd: #7a4bb5;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #141412;
    --surface: #1c1c1a;
    --ink: #ecebe6;
    --muted: #a09e96;
    --faint: #6f6d66;
    --line: #2d2c29;
    --accent: #8aa8ff;
    --accent-soft: #1f2740;
    --code-bg: #1f1f1c;
    --urdf: #8aa8ff;
    --mjcf: #f0956b;
    --sdformat: #7cc79a;
    --usd: #c3a1f0;
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #141412;
  --surface: #1c1c1a;
  --ink: #ecebe6;
  --muted: #a09e96;
  --faint: #6f6d66;
  --line: #2d2c29;
  --accent: #8aa8ff;
  --accent-soft: #1f2740;
  --code-bg: #1f1f1c;
  --urdf: #8aa8ff;
  --mjcf: #f0956b;
  --sdformat: #7cc79a;
  --usd: #c3a1f0;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 var(--sans);
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
code { font-family: var(--mono); font-size: 0.9em; background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 4px; }
[hidden] { display: none !important; }

.wrap { max-width: 860px; margin: 0 auto; padding: 0 16px; }

/* ---------- masthead */
.masthead { padding-top: 56px; padding-bottom: 8px; }
.kicker { font: 13px/1 var(--mono); color: var(--muted); margin: 0 0 14px; letter-spacing: 0.02em; }
h1 { font-size: clamp(32px, 6vw, 46px); line-height: 1.08; letter-spacing: -0.02em; margin: 0 0 14px; font-weight: 650; }
.lede { font-size: 18px; color: var(--muted); max-width: 640px; margin: 0; }

.hero {
  margin: 32px 0 8px;
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 20px;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px;
}
.hero svg { width: 100%; height: auto; max-height: 260px; display: block; }
.hero-ground { stroke: var(--line); stroke-width: 2; }
.hero-link-outline { stroke: var(--accent); stroke-width: 17; stroke-linecap: round; }
.hero-link-fill { stroke: var(--accent-soft); stroke-width: 14; stroke-linecap: round; }
.hero-link { fill: var(--accent-soft); stroke: var(--accent); stroke-width: 1.5; }
.hero-joint { fill: var(--surface); stroke: var(--mjcf); stroke-width: 2.5; }
.hero-label { font: 11px var(--mono); fill: var(--accent); }
.hero-joint-label { font: 11px var(--mono); fill: var(--mjcf); }
.hero-code {
  margin: 0;
  font: 12.5px/1.6 var(--mono);
  background: var(--code-bg);
  border-radius: 8px;
  padding: 14px 16px;
  overflow-x: auto;
  color: var(--ink);
}
.hero-code code { background: none; padding: 0; font-size: inherit; }
.hero-code .t { color: var(--muted); }
.hero-code .a { color: var(--mjcf); }
.hero-code .s { color: var(--accent); }

/* ---------- notice */
.notice {
  margin: 28px 0 0;
  padding: 12px 16px;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 8px 8px 0;
  font-size: 15px;
}
.notice p { margin: 0; }

/* ---------- start here */
.start h2, .section h2 { font-size: 22px; letter-spacing: -0.01em; margin: 0 0 6px; font-weight: 620; }
.start { margin-top: 40px; }
.start-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin-top: 14px; }
.start-card {
  display: flex; flex-direction: column; gap: 6px;
  padding: 16px; border: 1px solid var(--line); border-radius: 10px;
  background: var(--surface); color: var(--ink);
  transition: border-color 120ms ease, transform 120ms ease;
}
.start-card:hover { border-color: var(--accent); text-decoration: none; transform: translateY(-1px); }
.start-name { font-weight: 620; color: var(--accent); }
.start-why { font-size: 14.5px; color: var(--ink); }
.start-host { font: 12px var(--mono); color: var(--faint); margin-top: auto; }

/* ---------- toc + filter */
.toc { display: flex; flex-wrap: wrap; gap: 6px 16px; margin: 36px 0 0; padding: 14px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); font-size: 14.5px; }
.toc a { color: var(--muted); }
.toc a:hover { color: var(--accent); }

.filter { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin: 20px 0 0; }
.filter input {
  flex: 1 1 260px; min-width: 0;
  font: 15px var(--sans); color: var(--ink);
  background: var(--surface); border: 1px solid var(--line); border-radius: 8px;
  padding: 9px 12px;
}
.filter input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: transparent; }
.filter-chips { display: flex; gap: 6px; flex-wrap: wrap; }
.filter-empty { color: var(--muted); margin: 24px 0; }

.chip {
  display: inline-block; font: 11.5px/1 var(--mono); letter-spacing: 0.02em;
  padding: 4px 7px; border-radius: 999px; border: 1px solid currentColor;
  color: var(--muted); background: transparent; white-space: nowrap;
}
.chip-urdf { --chip: var(--urdf); color: var(--chip); }
.chip-mjcf { --chip: var(--mjcf); color: var(--chip); }
.chip-sdformat { --chip: var(--sdformat); color: var(--chip); }
.chip-usd { --chip: var(--usd); color: var(--chip); }
.chip-toggle { cursor: pointer; padding: 7px 10px; font-size: 12.5px; }
.chip-toggle[aria-pressed="true"] { background: var(--chip); border-color: var(--chip); color: var(--bg); }

/* ---------- sections (v1) */
.section { margin-top: 44px; scroll-margin-top: 16px; }
.num { font: 13px var(--mono); color: var(--faint); margin-right: 10px; font-weight: 400; }
.blurb { color: var(--muted); margin: 0 0 8px; max-width: 680px; }
.rows { list-style: none; margin: 0; padding: 0; }
.row { padding: 14px 0; border-bottom: 1px solid var(--line); }
.row:last-child { border-bottom: none; }
.row-head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 10px; }
.name { font-weight: 620; font-size: 16.5px; }
.chips { display: inline-flex; gap: 5px; flex-wrap: wrap; }
.desc { margin: 4px 0 0; }
.use, .caveat { display: block; font-size: 14.5px; color: var(--muted); margin-top: 2px; }
.caveat::before { content: "Note: "; font-weight: 600; }
.meta { font: 12.5px/1.4 var(--mono); color: var(--faint); margin: 6px 0 0; }

.footer { margin: 64px 0 40px; padding-top: 16px; border-top: 1px solid var(--line); font-size: 14px; color: var(--muted); }
.footer p { margin: 4px 0; }

.compare-wrap { overflow-x: auto; margin: 14px 0 6px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); }
.compare { width: 100%; border-collapse: collapse; font-size: 14px; }
.compare th, .compare td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
.compare thead th { font: 12px var(--mono); color: var(--muted); font-weight: 400; white-space: nowrap; }
.compare tbody tr:last-child th, .compare tbody tr:last-child td { border-bottom: none; }
.compare tbody th { font-weight: 400; white-space: nowrap; }

/* ---------- v2: gallery */
.v2 .section h2 { margin-top: 8px; }
.v2 .cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 14px; margin-top: 12px; }
.v2 .card { display: flex; flex-direction: column; border: 1px solid var(--line); border-radius: 10px; overflow: hidden; background: var(--surface); color: var(--ink); }
.v2 .card:hover { border-color: var(--accent); text-decoration: none; }
.v2 .card-img { aspect-ratio: 2 / 1; background: var(--code-bg); overflow: hidden; }
.v2 .card-img img { width: 100%; height: 100%; object-fit: cover; display: block; }
.v2 .card-fallback { height: 100%; display: grid; place-items: center; font: 14px var(--mono); color: var(--muted); }
.v2 .card-body { display: flex; flex-direction: column; gap: 6px; padding: 12px 14px 14px; }
.v2 .card .name { color: var(--accent); }
.v2 .card .desc { font-size: 14.5px; margin: 0; }
.v2 .card .meta { margin-top: auto; display: flex; flex-wrap: wrap; gap: 6px; align-items: center; }

/* ---------- v3: table */
.v3 { --sans: var(--mono); font-size: 14px; }
.v3 h1 { font-weight: 600; }
.v3 .table-wrap { overflow-x: auto; margin-top: 18px; border: 1px solid var(--line); border-radius: 8px; }
.v3 .table { width: 100%; border-collapse: collapse; font-size: 13px; }
.v3 .table th { text-align: left; font-weight: 600; color: var(--muted); padding: 9px 10px; border-bottom: 1px solid var(--line); background: var(--surface); position: sticky; top: 0; white-space: nowrap; }
.v3 .table th[data-key] { cursor: pointer; }
.v3 .table th[aria-sort="ascending"]::after { content: " ↑"; }
.v3 .table th[aria-sort="descending"]::after { content: " ↓"; }
.v3 .table td { padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
.v3 .table tr:last-child td { border-bottom: none; }
.v3 .table .desc { display: block; color: var(--muted); margin-top: 2px; font-size: 12.5px; min-width: 260px; }
.v3 .table .num { text-align: right; white-space: nowrap; font-family: var(--mono); color: var(--muted); }
.v3 .table .kind, .v3 .table .lic { color: var(--muted); white-space: nowrap; }

/* ---------- small screens */
@media (max-width: 720px) {
  .masthead { padding-top: 36px; }
  .hero { grid-template-columns: 1fr; padding: 14px; }
  .hero svg { max-width: 300px; margin: 0 auto; }
  .start-grid { grid-template-columns: 1fr; }
  .lede { font-size: 16.5px; }
}

.v3 .wrap { max-width: 1120px; }