:root {
  --bg: #ffffff;
  --surface: #f7f8fa;
  --ink: #172033;
  --ink-soft: #586579;
  --ink-faint: #7b8594;
  --line: #dfe3e8;
  --accent: #1768e5;
  --accent-soft: #edf4ff;
  --max: 1120px;
  color-scheme: light;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Helvetica Neue", Helvetica, Arial, "Noto Sans SC", "Microsoft YaHei", sans-serif;
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
button { font: inherit; }
img, video { display: block; max-width: 100%; }
h1, h2, h3, h4, p { margin-top: 0; }

.skip-link { position: fixed; top: -50px; left: 16px; z-index: 100; padding: 8px 12px; background: var(--ink); color: white; }
.skip-link:focus { top: 12px; }
.section-shell { width: min(calc(100% - 48px), var(--max)); margin-inline: auto; }

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  align-items: center;
  min-height: 62px;
  padding: 8px max(24px, calc((100vw - var(--max)) / 2));
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(10px);
}
.brand { display: flex; align-items: center; gap: 10px; font-size: 18px; font-weight: 700; letter-spacing: -.02em; }
.brand img { width: 33px; height: 33px; border-radius: 5px; object-fit: cover; }
.main-nav { display: flex; gap: 26px; margin-left: auto; }
.main-nav a { color: var(--ink-soft); font-size: 15px; }
.main-nav a:hover, .main-nav a.active { color: var(--accent); }
.header-actions { display: flex; align-items: center; gap: 12px; margin-left: 28px; }
.text-button, .github-link { padding: 5px 0; border: 0; border-bottom: 1px solid transparent; background: transparent; color: var(--ink-soft); font-size: 15px; cursor: pointer; }
.github-link { color: var(--ink); font-weight: 600; }
.text-button:hover, .github-link:hover { border-color: currentColor; color: var(--accent); }

.hero { padding: 78px 0 58px; text-align: center; }
.hero-copy { max-width: 880px; margin: 0 auto; }
.eyebrow { color: var(--accent); font-size: 16px; font-weight: 700; letter-spacing: .12em; }
h1 { max-width: 900px; margin: 16px auto 22px; font-size: clamp(44px, 6.5vw, 72px); font-weight: 700; line-height: 1.04; letter-spacing: -.045em; }
h1 em { color: var(--accent); font-style: normal; }
.hero-lead { max-width: 760px; margin: 0 auto; color: var(--ink-soft); font-size: clamp(17px, 2vw, 20px); line-height: 1.55; }
.hero-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 18px; margin-top: 27px; }
.button { display: inline-flex; align-items: center; padding: 7px 0; border-bottom: 1px solid var(--ink-faint); font-size: 15px; font-weight: 600; }
.button:hover { border-color: var(--accent); color: var(--accent); }
.button-primary { border-color: var(--accent); color: var(--accent); }
.hero-meta { margin-top: 20px; color: var(--ink-faint); font-size: 15px; }

.hero-showcase { max-width: 1020px; margin: 44px auto 0; text-align: left; }
.hero-showcase-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 24px; margin: 0 42px 12px; }
.hero-showcase-heading strong { font-size: 16px; }
.hero-showcase-heading span { color: var(--ink-faint); font-size: 15px; }
.hero-carousel-shell { display: grid; grid-template-columns: 30px minmax(0, 1fr) 30px; align-items: center; gap: 12px; }
.hero-carousel { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.hero-demo-card video { width: 100%; aspect-ratio: 16 / 9; border-radius: 5px; background: #0b0f17; object-fit: contain; }
.hero-demo-card > div { padding: 9px 1px 0; }
.hero-demo-card strong, .hero-demo-card span { display: block; }
.hero-demo-card strong { overflow: hidden; font-size: 15px; text-overflow: ellipsis; white-space: nowrap; }
.hero-demo-card span { color: var(--ink-faint); font-size: 15px; }
.carousel-button { width: 30px; height: 46px; padding: 0; border: 0; background: transparent; color: var(--ink-soft); font-size: 20px; cursor: pointer; }
.carousel-button:hover { color: var(--accent); }
.hero-carousel-status { margin-top: 8px; color: var(--ink-faint); font-size: 15px; text-align: center; }

.scope-statement { margin-top: 0; margin-bottom: 8px; padding: 18px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); color: var(--ink-soft); font-size: 17px; }
.scope-safety { margin-bottom: 0; padding-top: 0; border-top: 0; color: var(--ink-faint); font-size: 15px; }

.section { padding: 88px 0; scroll-margin-top: 62px; }
.section-muted { background: var(--surface); }
.section-heading, .subsection-heading { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(260px, .6fr); align-items: end; gap: 64px; margin-bottom: 38px; }
.section-heading h2 { max-width: 730px; margin: 7px 0 0; font-size: clamp(34px, 4.5vw, 48px); font-weight: 680; line-height: 1.12; letter-spacing: -.035em; }
.section-heading > p, .subsection-heading > p { margin: 0; color: var(--ink-soft); font-size: 16px; }
.architecture-figure { margin: 0 0 42px; }
.architecture-figure img { width: 100%; border: 1px solid var(--line); border-radius: 5px; background: white; }
.architecture-figure-model { margin-bottom: 48px; }

.framework-flow { display: grid; grid-template-columns: repeat(5, 1fr); border-bottom: 1px solid var(--line); }
.framework-node { min-height: 102px; padding: 14px 12px; border: 0; border-bottom: 2px solid transparent; background: transparent; color: var(--ink-soft); text-align: left; cursor: pointer; }
.framework-node:hover, .framework-node.active { border-bottom-color: var(--accent); color: var(--ink); }
.node-index { display: block; margin-bottom: 14px; color: var(--accent); font-size: 16px; }
.framework-node strong, .framework-node small { display: block; }
.framework-node strong { font-size: 18px; }
.framework-node small { margin-top: 3px; color: var(--ink-faint); font-size: 17px; }
.detail-panel { display: grid; grid-template-columns: 1.2fr .8fr; gap: 54px; min-height: 210px; padding: 30px 12px; border-bottom: 1px solid var(--line); }
.detail-panel h3 { margin: 6px 0 10px; font-size: 25px; letter-spacing: -.025em; }
.detail-panel p { max-width: 650px; margin: 0; color: var(--ink-soft); font-size: 16px; }
.detail-list { margin: 0; padding: 0; list-style: none; }
.detail-list li { padding: 8px 0; border-bottom: 1px solid var(--line); color: var(--ink-soft); font-size: 15px; }
.detail-list li::before { content: "→"; margin-right: 9px; color: var(--accent); }
.principle-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 36px; margin-top: 34px; }
.principle-grid article { padding-top: 14px; border-top: 1px solid var(--ink); }
.principle-grid article > span { color: var(--accent); font-size: 16px; }
.principle-grid h3 { margin: 14px 0 7px; font-size: 19px; }
.principle-grid p { margin: 0; color: var(--ink-soft); font-size: 17px; }

.model-layout { display: grid; grid-template-columns: 210px 1fr; gap: 36px; }
.model-tabs { display: grid; align-content: start; border-right: 1px solid var(--line); }
.model-tab { padding: 11px 18px 11px 0; border: 0; background: transparent; color: var(--ink-soft); font-size: 18px; text-align: left; cursor: pointer; }
.model-tab:hover, .model-tab.active { color: var(--accent); }
.model-detail { min-height: 210px; padding: 4px 0; }
.model-detail h3 { margin: 7px 0 12px; font-size: 27px; letter-spacing: -.03em; }
.model-detail p { max-width: 720px; color: var(--ink-soft); font-size: 16px; }
.tag-list { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 22px; }
.tag { color: var(--ink-faint); font-size: 15px; }
.tag::before { content: "#"; color: var(--accent); }

.data-showcase { min-height: 500px; padding: 44px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.data-heading h2 { max-width: none; margin: 18px 0 0; color: #111; font-size: clamp(48px, 5.5vw, 72px); font-weight: 700; line-height: 1.06; letter-spacing: -.055em; }
.data-lead { max-width: none; margin: 24px 0 38px; color: #111; font-size: clamp(18px, 1.8vw, 22px); line-height: 1.6; }
.data-flow { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(280px, .7fr) minmax(260px, .85fr); align-items: center; gap: 24px; }
.data-flow > * { min-width: 0; }
.data-datasets { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr) minmax(0, 1fr); gap: 14px 16px; }
.data-dataset { display: flex; align-items: center; justify-content: center; min-height: 52px; padding: 9px 10px; border: 1px solid var(--line); border-radius: 7px; color: var(--ink-soft); font-size: 14px; line-height: 1.35; text-align: center; white-space: nowrap; }
.data-dataset strong { color: #111; font-size: 15px; }
.data-transfer { display: flex; flex-direction: column; align-items: stretch; gap: 9px; color: #111; }
.data-transfer-label { font-size: 15px; font-weight: 600; line-height: 1.4; text-align: center; white-space: nowrap; }
.data-transfer-arrow { display: block; width: 100%; height: 28px; color: #111; }
.data-format { text-align: center; }
.data-format-icon { width: 44px; height: 52px; margin: 0 auto 9px; color: var(--ink-faint); }
.data-format h3 { margin: 0; color: #111; font-size: clamp(34px, 3.7vw, 50px); font-weight: 700; line-height: 1; letter-spacing: -.055em; }
.data-format strong { display: block; margin-top: 12px; color: var(--accent); font-size: clamp(18px, 1.8vw, 25px); line-height: 1.2; }
.data-format p { margin: 14px 0 0; color: var(--ink-soft); font-size: 16px; line-height: 1.65; }

.benchmark-switcher, .demo-filter { display: flex; flex-wrap: wrap; gap: 18px; margin-bottom: 26px; border-bottom: 1px solid var(--line); }
.benchmark-tab, .demo-filter-button, .benchmark-view-tab { padding: 8px 0; border: 0; border-bottom: 2px solid transparent; background: transparent; color: var(--ink-soft); font-size: 15px; cursor: pointer; }
.benchmark-tab:hover, .benchmark-tab.active, .demo-filter-button:hover, .demo-filter-button.active, .benchmark-view-tab:hover, .benchmark-view-tab.active { border-bottom-color: var(--accent); color: var(--accent); }
.benchmark-panel { background: transparent; }
.benchmark-top { display: flex; align-items: start; justify-content: space-between; gap: 20px; margin-bottom: 22px; }
.benchmark-top h3 { margin: 0 0 2px; font-size: 26px; }
.benchmark-status, .benchmark-source { color: var(--accent); font-size: 15px; }
.benchmark-view-switcher { display: flex; gap: 16px; margin-bottom: 22px; }
.benchmark-view-heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 12px; }
.benchmark-view-heading span, .comparison-heading span { color: var(--ink-faint); font-size: 16px; letter-spacing: .08em; text-transform: uppercase; }
.benchmark-view-heading h4 { margin: 2px 0 0; font-size: 18px; }
.benchmark-view-heading p { margin: 0; color: var(--ink-faint); font-size: 15px; }
.metrics-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; padding: 18px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.metric-label { display: block; color: var(--ink-faint); font-size: 16px; }
.metric-value { display: block; margin-top: 4px; color: var(--accent); font-size: clamp(22px, 2.6vw, 28px); letter-spacing: -.025em; }
.benchmark-description { margin: 18px 0 0; color: var(--ink-soft); font-size: 15px; }
.comparison-heading { display: flex; justify-content: space-between; margin: 27px 0 8px; }
.comparison-heading small { color: var(--ink-faint); font-size: 16px; }
.comparison-list { border-top: 1px solid var(--line); }
.comparison-row { display: grid; grid-template-columns: minmax(210px, 1.2fr) minmax(0, 2fr); gap: 22px; padding: 12px 4px; border-bottom: 1px solid var(--line); }
.comparison-row.highlight { background: var(--accent-soft); }
.comparison-method strong { display: block; font-size: 17px; font-weight: 500; }
.comparison-method strong.sota { font-weight: 700; }
.comparison-meta { display: flex; flex-wrap: wrap; gap: 3px 12px; margin-top: 2px; }
.comparison-meta span, .comparison-meta a { display: block; color: var(--ink-faint); font-size: 16px; }
.comparison-meta a:hover { color: var(--accent); }
.comparison-row.highlight .comparison-method strong { color: var(--accent); }
.comparison-values { display: grid; grid-template-columns: repeat(var(--metric-count), minmax(0, 1fr)); gap: 12px; }
.comparison-value { text-align: right; }
.comparison-value span { display: block; color: var(--ink-faint); font-size: 16px; }
.comparison-value strong { display: block; font-size: 17px; font-weight: 500; font-variant-numeric: tabular-nums; }
.comparison-value strong.sota { font-weight: 700; }

.demo-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 30px 34px; }
.demo-card video { width: 100%; aspect-ratio: 16 / 9; border-radius: 5px; background: #090d14; object-fit: contain; }
.demo-card > div { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; padding: 9px 1px 0; }
.demo-card strong { font-size: 16px; }
.demo-card span { color: var(--ink-faint); font-size: 15px; }

.roadmap { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; }
.roadmap-item { padding-top: 14px; border-top: 1px solid var(--line); }
.roadmap-item:first-child { border-color: var(--accent); }
.roadmap-marker { color: var(--accent); font-size: 17px; font-weight: 700; }
.roadmap-item h3 { margin: 16px 0 7px; font-size: 19px; }
.roadmap-item p { color: var(--ink-soft); font-size: 17px; }
.roadmap-state { color: var(--ink-faint); font-size: 16px; text-transform: uppercase; letter-spacing: .07em; }

.section-dark { background: var(--surface); color: var(--ink); }
.section-dark .section-heading > p { color: var(--ink-soft); }
.docs-grid { display: grid; grid-template-columns: repeat(2, 1fr); column-gap: 48px; border-top: 1px solid var(--line); }
.docs-card { min-height: 145px; padding: 20px 2px; border-bottom: 1px solid var(--line); }
.docs-card:hover h3 { color: var(--accent); }
.docs-label { color: var(--accent); font-size: 14px; letter-spacing: .08em; }
.docs-card h3 { margin: 15px 0 5px; font-size: 18px; }
.docs-card p { margin-bottom: 10px; color: var(--ink-soft); font-size: 15px; }
.docs-link { color: var(--accent); font-size: 15px; }

.site-footer { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; min-height: 104px; border-top: 1px solid var(--line); color: var(--ink-faint); font-size: 15px; }
.site-footer strong { display: block; color: var(--ink); font-size: 16px; }
.site-footer strong + span { display: block; }
.footer-links { display: flex; gap: 20px; color: var(--ink-soft); }
.footer-links a:hover { color: var(--accent); }
.footer-note { text-align: right; }
.noscript { position: fixed; right: 16px; bottom: 16px; left: 16px; z-index: 40; padding: 12px; border: 1px solid var(--line); background: white; }

@media (max-width: 760px) {
  .data-flow { grid-template-columns: 1fr; gap: 28px; }
  .data-transfer { width: min(360px, 100%); margin-inline: auto; }
  .data-format { padding-top: 28px; border-top: 1px solid var(--line); }
}

@media (max-width: 900px) {
  .site-header { flex-wrap: wrap; }
  .main-nav { order: 3; width: 100%; margin: 0; overflow-x: auto; padding-top: 6px; }
  .header-actions { margin-left: auto; }
  .section-heading, .subsection-heading { grid-template-columns: 1fr; gap: 16px; }
  .framework-flow { grid-template-columns: repeat(5, minmax(145px, 1fr)); overflow-x: auto; }
  .detail-panel, .model-layout { grid-template-columns: 1fr; }
  .model-tabs { display: flex; overflow-x: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .model-tab { flex: 1 0 145px; }
  .scope-statement { font-size: 16px; }
  .principle-grid { grid-template-columns: 1fr; }
  .data-showcase { padding: 42px 0; }
}

@media (max-width: 640px) {
  .section-shell { width: min(calc(100% - 30px), var(--max)); }
  .site-header { padding-inline: 15px; }
  .main-nav { gap: 18px; }
  .github-link { display: none; }
  .hero { padding-top: 55px; }
  h1 { font-size: clamp(40px, 12vw, 56px); }
  .hero-lead { font-size: 16px; }
  .hero-showcase { margin-top: 36px; }
  .hero-showcase-heading { align-items: start; flex-direction: column; gap: 3px; margin-inline: 36px; }
  .hero-carousel-shell { grid-template-columns: 25px minmax(0, 1fr) 25px; gap: 6px; }
  .hero-carousel { grid-template-columns: 1fr; }
  .hero-demo-card:nth-child(n+2) { display: none; }
  .carousel-button { width: 25px; }
  .section { padding: 70px 0; }
  .section-heading h2 { font-size: 34px; }
  .detail-panel { padding-inline: 0; }
  .data-heading h2 { font-size: 42px; }
  .data-lead { font-size: 18px; }
  .benchmark-top, .benchmark-view-heading, .comparison-heading { align-items: start; flex-direction: column; }
  .metrics-grid { grid-template-columns: repeat(2, 1fr); }
  .comparison-row { grid-template-columns: 1fr; }
  .comparison-value { text-align: left; }
  .demo-grid, .roadmap, .docs-grid { grid-template-columns: 1fr; }
  .site-footer { grid-template-columns: 1fr; gap: 8px; padding: 26px 0; }
  .footer-note { text-align: left; }
}