:root {
  --ink: #172b3d;
  --muted: #5d6d7b;
  --blue: #386687;
  --accent: #b75a2d;
  --line: #dbe3e9;
  --tint: #f3f6f8;
  --dark: #111e2b;
  --max: 1600px;
  --heading: "Manrope", Arial, sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: #fff; color: var(--ink); font: 400 18px/1.65 "DM Sans", Arial, sans-serif; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button { font: inherit; }
img, video { display: block; width: 100%; }
figure, p { margin: 0; }
h1, h2, h3 { font-family: var(--heading); text-wrap: balance; }
h2 { font-size: clamp(36px, 3.5vw, 56px); line-height: 1.16; letter-spacing: -.035em; font-weight: 700; margin: 0; }
h3 { font-size: 24px; line-height: 1.35; letter-spacing: -.02em; margin: 0 0 10px; }
p { text-wrap: pretty; }
a:focus-visible, button:focus-visible, video:focus-visible { outline: 3px solid #df9657; outline-offset: 5px; }
.container { width: min(var(--max), calc(100% - 64px)); margin-inline: auto; }
.narrow { max-width: 1060px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.accent { color: var(--accent); }
.progress { position: fixed; inset: 0 0 auto; height: 3px; z-index: 100; }
.progress span { display: block; height: 100%; width: 0; background: var(--accent); }
.nav { position: fixed; inset: 0 0 auto; z-index: 90; background: rgb(255 255 255 / 94%); backdrop-filter: blur(16px); border-bottom: 1px solid rgb(23 43 61 / 8%); }
.nav-inner { width: min(1640px, calc(100% - 48px)); height: 68px; display: flex; align-items: center; gap: 24px; margin: auto; }
.brand { display: flex; align-items: center; gap: 10px; font: 800 19px/1 var(--heading); letter-spacing: .04em; }
.brand-mark { display: flex; align-items: end; gap: 3px; height: 24px; }
.brand-mark i { width: 6px; height: 12px; border-radius: 4px; background: #668bab; }
.brand-mark i:nth-child(2) { height: 22px; background: #8b80a0; }
.brand-mark i:nth-child(3) { height: 17px; background: #d79566; }
.nav-links { display: flex; align-items: center; gap: 20px; margin-left: auto; font-size: 14px; font-weight: 600; }
.nav-links a { color: var(--muted); }
.nav-links a:hover, .nav-links a[aria-current] { color: var(--accent); }
.nav-github { border: 1px solid var(--line); padding: 7px 15px; border-radius: 6px; font-size: 12px; font-weight: 600; }
.nav-toggle { display: none; border: 0; background: none; width: 42px; height: 42px; margin-left: auto; }
.nav-toggle span { display: block; height: 2px; width: 23px; margin: 6px auto; background: var(--ink); }
.hero { --hero-accent: #c4510b; padding: 102px 0 52px; background: #fff; }
.hero .container { width: min(var(--max), calc(100% - 64px)); }
.hero-copy { text-align: center; }
.orb { display: none; }
.kicker, .eyebrow { color: var(--blue); font-size: 14px; font-weight: 700; text-transform: uppercase; letter-spacing: .12em; }
.eyebrow { font-family: var(--heading); font-size: clamp(22px, 1.6vw, 28px); line-height: 1.4; font-weight: 800; letter-spacing: .045em; }
.hero-wordmark { display: flex; justify-content: center; align-items: center; gap: 22px; color: #333; font: 800 clamp(60px, 6vw, 86px)/1 var(--heading); letter-spacing: -.055em; }
.wordmark-accent { color: var(--hero-accent); }
.hero-wordmark .brand-mark { height: 62px; gap: 7px; }
.hero-wordmark .brand-mark i { width: 16px; height: 32px; border-radius: 7px; }
.hero-wordmark .brand-mark i:nth-child(2) { height: 60px; }
.hero-wordmark .brand-mark i:nth-child(3) { height: 46px; background: var(--hero-accent); }
.hero h1 { max-width: 1250px; margin: 22px auto 18px; color: #333; font-weight: 800; font-size: clamp(34px, 3.5vw, 52px); line-height: 1.18; letter-spacing: -.025em; }
.hero-lead { font-size: 23px; color: #5d6063; }
.authors { display: grid; justify-content: center; align-items: baseline; row-gap: 8px; width: fit-content; max-width: 100%; margin: 26px auto 0; color: var(--hero-accent); font-size: clamp(20px, 1.8vw, 25px); font-weight: 500; line-height: 1.65; }
.author-row { display: flex; justify-content: center; align-items: baseline; gap: clamp(24px, 3vw, 48px); }
.author-item { white-space: nowrap; }
.author-separator { display: none; }
.authors a { color: inherit; white-space: nowrap; text-decoration: underline; text-decoration-thickness: 1px; text-decoration-color: rgb(196 81 11 / 30%); text-underline-offset: 5px; transition: color .18s ease, text-decoration-color .18s ease; }
.authors a:hover, .authors a:focus-visible { color: #8d3906; text-decoration-color: currentColor; }
.hero-affiliations { display: flex; justify-content: center; align-items: center; gap: clamp(30px, 5vw, 72px); margin: 28px auto; }
.hero-affiliations img { flex-shrink: 0; object-fit: contain; height: auto; }
.hero-affiliations .affiliation-bigai { width: 270px; }
.hero-affiliations .affiliation-sharpa { width: 190px; }
.affiliation-sjtu { display: flex; align-items: center; gap: 14px; text-align: left; }
.affiliation-sjtu img { width: 64px; }
.affiliation-sjtu span { font-size: 13px; line-height: 1.45; color: #454545; font-weight: 500; }
.hero-actions { display: flex; align-items: stretch; justify-content: center; gap: 14px; flex-wrap: wrap; margin: 24px 0 36px; }
.button { display: inline-flex; align-items: center; gap: 8px; border: 1px solid var(--line); padding: 10px 18px; border-radius: 6px; font-size: 15px; font-weight: 600; background: #fff; }
.button svg { width: 15px; height: 15px; fill: currentColor; }
.button.ghost { border-color: transparent; color: var(--blue); background: none; }
.button.disabled { background: #e5eaee; border-color: #e5eaee; color: #5d6975; }
.hero-actions .button { justify-content: center; gap: 10px; min-height: 58px; padding: 14px 28px; border-radius: 999px; font-size: 20px; font-weight: 600; line-height: 1.35; white-space: nowrap; box-shadow: none; }
.hero-actions .button svg { flex-shrink: 0; width: 21px; height: 21px; }
.hero-actions .button .outline-icon { fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.hero-actions .button.secondary { min-width: 144px; background: #353535; border-color: #353535; color: #fff; }
.hero-actions .button.ghost { background: #353535; border-color: #353535; color: #fff; }
.hero-actions .button.disabled { background: #535353; border-color: #535353; color: #fff; box-shadow: none; }
.button-note { padding: 4px 8px; border-radius: 999px; background: #6a6a6a; color: #fff; font-size: 12px; font-weight: 500; }
.hero-actions a.button { transition: transform .18s ease, background .18s ease, box-shadow .18s ease; }
.hero-actions a.button:hover { transform: translateY(-2px); box-shadow: 0 7px 18px rgb(23 43 61 / 13%); }
.hero-actions .button.secondary:hover, .hero-actions .button.ghost:hover { background: #1c1c1c; }
.overview-video { width: 100%; margin: auto; border: 1px solid #d0d9e1; border-radius: 12px; overflow: hidden; background: #111e2b; box-shadow: 0 16px 50px #172b3d14; scroll-margin-top: 82px; }
.overview-video video { aspect-ratio: 16 / 9; object-fit: contain; }
.section { padding: 84px 0; scroll-margin-top: 68px; }
.section.tinted { background: var(--tint); }
.chapter { min-height: calc(100svh - 68px); padding: 42px 0; display: flex; align-items: center; border-top: 1px solid var(--line); }
.chapter-inner { display: flex; flex-direction: column; gap: 32px; }
.chapter-heading { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding-bottom: 16px; border-bottom: 1px solid var(--line); }
.chapter-topic { color: #647585; font-size: 15px; }
.motivation-layout { display: grid; grid-template-columns: .9fr 1.1fr; align-items: center; gap: 56px; }
.motivation-copy h2 { margin-bottom: 24px; }
.motivation-copy h2 .accent { display: block; text-wrap: balance; }
.motivation-copy .lead { font-size: clamp(21px, 1.5vw, 25px); color: #354e61; line-height: 1.6; margin-bottom: 20px; }
.motivation-copy > p:not(.lead) { color: var(--muted); font-size: 19px; }
.takeaway { margin-top: 26px; padding-left: 18px; border-left: 3px solid #d9a27c; }
.takeaway span, .next-step > span { display: block; text-transform: uppercase; font-size: 13px; letter-spacing: .1em; font-weight: 700; color: var(--accent); margin-bottom: 8px; }
.takeaway p { font-size: 19px; font-weight: 500; }
.motivation-figure img { max-height: min(70svh, 700px); object-fit: contain; }
figcaption { color: var(--muted); font-size: 16px; margin-top: 14px; line-height: 1.5; }
.motivation-figure figcaption { text-align: center; }
.section-head { display: grid; grid-template-columns: 1.25fr .75fr; align-items: end; gap: 56px; margin-bottom: 32px; }
.section-head .eyebrow { margin-bottom: 12px; }
.section-head > p { font-size: 20px; color: var(--muted); }
.chapter .section-head { margin-bottom: 0; }
.paper-figure { margin: 0; background: #fff; padding: 14px; border-radius: 8px; border: 1px solid var(--line); }
.system-figure img { height: clamp(260px, 37svh, 420px); object-fit: contain; }
.dataset-strip { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, .85fr); gap: 48px; align-items: center; padding-top: 8px; }
.dataset-strip figure { background: #fff; padding: 14px; border: 1px solid var(--line); border-radius: 8px; }
.dataset-strip figure img { width: 100%; height: auto; }
.dataset-strip h3 { margin-bottom: 18px; font-size: clamp(28px, 2vw, 34px); }
.dataset-strip p { color: var(--muted); font-size: 22px; max-width: 680px; }
.dataset-counts { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-top: 30px; }
.dataset-counts div { display: flex; flex-direction: column; gap: 10px; }
.dataset-counts strong { font: 800 48px/1.1 var(--heading); color: var(--blue); }
.dataset-counts span { color: var(--muted); font-size: 17px; line-height: 1.5; }
.dataset-modalities { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 28px; font-size: 16px; font-weight: 500; color: var(--blue); }
.dataset-modalities span { padding: 5px 12px; border: 1px solid #cddbe5; border-radius: 5px; background: #eaf0f5; }
.model-layout { display: grid; grid-template-columns: minmax(0, 1fr) 310px; gap: 32px; align-items: center; }
.method-figure img { height: clamp(350px, 53svh, 570px); object-fit: contain; }
.method-notes { display: grid; grid-template-columns: 1fr; gap: 22px; }
.method-notes article { border-top: 2px solid #cbd8e2; padding-top: 14px; }
.method-notes span { color: var(--accent); font-size: 13px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; }
.method-notes h3 { font-size: 22px; margin: 8px 0; }
.method-notes p { color: var(--muted); font-size: 17px; }
.demos-section { background: var(--dark); color: #f3f6f8; }
.light .eyebrow { color: #b7d4e9; }
.demos-heading { grid-template-columns: 1fr; }
.section-head.light > p { color: #acbbc7; }
.demo-tabs { display: flex; gap: 7px; flex-wrap: wrap; margin-bottom: 20px; }
.demo-tabs button { padding: 12px 22px; border: 1px solid #405365; border-radius: 6px; color: #becbd5; background: transparent; font-size: 17px; cursor: pointer; }
.demo-tabs button[aria-selected="true"] { background: #f1e1d5; border-color: #f1e1d5; color: #59381f; }
.demo-tabs button:hover { border-color: #d8a378; }
.demo-stage { border: 1px solid #3b4d5e; border-radius: 10px; overflow: hidden; background: #0b141e; }
.demo-stage video { aspect-ratio: 16 / 9; background: #0b141e; }
.demo-caption { display: block; padding: 28px 34px 32px; margin: 0; line-height: 1.65; }
.demo-caption h3 { font-size: 28px; margin: 7px 0 10px; color: #f3f6f8; }
.demo-caption p { font-size: 20px; color: #b9c9d5; max-width: 1200px; }
.demo-caption .task-eyebrow { font-size: 13px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: #ddae86; }
.demo-footnote { font-size: 15px; color: #a9bac7; margin-top: 18px; }
.generalization-section { background: #182b3b; border-top: 1px solid #3b4d5e; }
.results-layout { display: grid; grid-template-columns: minmax(0, 1fr) 330px; gap: 28px; }
.result-table-wrap { overflow-x: auto; background: #fff; border: 1px solid var(--line); border-radius: 8px; padding: 10px; }
table { border-collapse: collapse; width: 100%; min-width: 650px; font-size: 18px; }
th, td { text-align: center; padding: 16px 10px; border-bottom: 1px solid #e8edf1; }
th:first-child, td:first-child { text-align: left; }
th { color: var(--muted); font-size: 14px; text-transform: uppercase; letter-spacing: .04em; }
.ours td { font-weight: 700; background: #edf3f7; color: var(--blue); border-bottom: 0; }
.result-callouts { display: grid; gap: 12px; }
.result-callouts div { display: flex; align-items: center; gap: 16px; padding: 13px 20px; background: #fff; border: 1px solid var(--line); border-radius: 8px; }
.result-callouts strong { font: 700 38px/1 var(--heading); color: var(--accent); min-width: 80px; }
.result-callouts span { font-size: 16px; color: var(--muted); }
.scaling { margin: 30px 0 0; border: 1px solid var(--line); border-radius: 8px; background: #fff; padding: 20px; }
.scaling img { max-height: 480px; object-fit: contain; }
.outlook { background: #fffaf5; }
.outlook h2 { max-width: 1280px; margin: 6px 0 10px; }
.outlook-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; }
.outlook-grid article { padding: 22px 0; border-top: 1px solid #dbcbbd; }
.outlook-number { font: 500 16px var(--heading); color: var(--accent); }
.outlook-grid h3 { font-size: 29px; margin: 18px 0; }
.outlook-grid article > p { font-size: 21px; color: var(--muted); max-width: 700px; }
.next-step { margin-top: 28px; padding-left: 18px; border-left: 2px solid #cc9972; }
.next-step p { color: #3c5263; font-size: 20px; }
.outlook-closing { border-top: 1px solid #dbcbbd; padding-top: 22px; color: var(--accent); font-size: 20px; }
.citation { text-align: center; padding: 65px 0; border-top: 1px solid var(--line); }
.citation h2 { font-size: 32px; margin: 18px 0; }
.citation .lead { font-size: 19px; color: var(--muted); }
footer { padding: 28px 0; background: var(--dark); color: #adbdc9; font-size: 14px; }
footer .container { display: flex; justify-content: space-between; gap: 20px; }
@media (min-width: 1000px) and (max-height: 800px) {
  .chapter { padding: 28px 0; }
  .chapter-inner { gap: 20px; }
  .chapter h2 { font-size: 40px; }
  .system-figure img { height: 280px; }
  .method-figure img { height: 400px; }
  .motivation-copy .lead { font-size: 21px; }
}
@media (min-width: 1051px) and (max-width: 1350px) {
  .nav-links { gap: 13px; font-size: 13px; }
  .nav-inner { gap: 16px; }
  .dataset-strip { gap: 32px; }
  .model-layout { grid-template-columns: minmax(0, 1fr) 275px; gap: 24px; }
  .section-head { gap: 32px; }
}
@media (max-width: 1050px) {
  .nav-links { gap: 10px; font-size: 12px; }
  .nav-inner { gap: 16px; }
  .motivation-layout { gap: 30px; }
  .dataset-strip { gap: 28px; }
  .dataset-strip p { font-size: 20px; }
  .dataset-counts strong { font-size: 40px; }
  .results-layout { grid-template-columns: 1fr; }
  .result-callouts { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 800px) {
  .container, .hero .container { width: calc(100% - 36px); }
  .nav-links, .nav-github { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open { position: absolute; display: flex; flex-direction: column; align-items: stretch; inset: 68px 12px auto; padding: 20px; gap: 16px; background: #fff; border: 1px solid var(--line); border-radius: 8px; box-shadow: 0 20px 40px #172b3d22; font-size: 14px; }
  .hero { padding-top: 98px; }
  .hero h1 { font-size: clamp(28px, 5.8vw, 42px); }
  .hero-wordmark { font-size: 62px; gap: 16px; }
  .hero-wordmark .brand-mark { transform: scale(.8); transform-origin: right center; }
  .hero-lead { font-size: 18px; }
  .authors { grid-template-columns: repeat(2, max-content); column-gap: 32px; row-gap: 7px; margin-top: 22px; font-size: 19px; line-height: 1.6; }
  .author-row { display: contents; }
  .hero-affiliations { gap: 26px; flex-wrap: wrap; }
  .hero-affiliations .affiliation-bigai { width: 220px; }
  .hero-affiliations .affiliation-sharpa { width: 150px; }
  .section, .chapter { padding: 52px 0; min-height: auto; }
  .chapter-topic { display: none; }
  .chapter-inner { gap: 24px; }
  .motivation-layout, .section-head { grid-template-columns: 1fr; gap: 22px; }
  .motivation-copy h2 { margin-bottom: 20px; }
  .motivation-figure img { max-height: 480px; }
  .system-figure img, .method-figure img { height: auto; max-height: none; }
  .dataset-strip { grid-template-columns: 1fr; gap: 28px; }
  .model-layout { grid-template-columns: 1fr; }
  .method-notes { grid-template-columns: repeat(3, 1fr); }
  .method-notes { gap: 18px; }
  .method-notes h3 { font-size: 20px; }
  .outlook-grid { gap: 28px; }
}
@media (max-width: 540px) {
  .kicker { font-size: 11px; }
  .eyebrow { font-size: 20px; letter-spacing: .035em; }
  h2 { font-size: 33px; }
  .hero-actions { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; max-width: 400px; margin: 24px auto; }
  .hero-actions .button { min-width: 0; min-height: 52px; padding: 12px 10px; gap: 7px; font-size: 17px; }
  .hero-actions .button.secondary { min-width: 0; }
  .hero-actions .button.ghost { grid-column: 1 / -1; }
  .hero-actions .button svg { width: 19px; height: 19px; }
  .button-note { font-size: 11px; padding: 4px 6px; }
  .authors { column-gap: 24px; font-size: 18px; }
  .hero-wordmark { font-size: 56px; }
  .hero-affiliations { gap: 20px 24px; margin-block: 24px; }
  .hero-affiliations .affiliation-bigai { width: 168px; }
  .hero-affiliations .affiliation-sharpa { width: 112px; }
  .affiliation-sjtu { justify-content: center; width: 100%; }
  .affiliation-sjtu img { width: 50px; }
  .affiliation-sjtu span { font-size: 12px; }
  .button { font-size: 13px; padding: 9px 12px; }
  .motivation-copy .lead { font-size: 20px; }
  .dataset-strip figure { padding: 8px; }
  .dataset-counts { gap: 20px; }
  .dataset-counts span { font-size: 16px; }
  .method-notes, .outlook-grid { grid-template-columns: 1fr; }
  .method-notes h3 { font-size: 21px; }
  .demo-tabs { gap: 6px; }
  .demo-tabs button { font-size: 14px; padding: 9px 12px; }
  .demo-caption { padding: 20px; }
  .demo-caption h3 { font-size: 24px; }
  .demo-caption p { font-size: 18px; }
  .result-callouts { grid-template-columns: 1fr; }
  .outlook-grid { gap: 0; }
  footer .container { flex-direction: column; gap: 6px; }
}
@media (max-width: 360px) {
  .hero-affiliations .affiliation-bigai { width: 150px; }
  .hero-affiliations .affiliation-sharpa { width: 100px; }
  .hero-actions .button { padding-inline: 8px; gap: 6px; font-size: 16px; }
  .hero-actions .button.disabled svg { display: none; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } .hero-actions a.button, .authors a { transition: none; } .hero-actions a.button:hover { transform: none; } }