:root {
  --paper: #f7f8f5;
  --white: #fcfdfb;
  --ink: #17201e;
  --muted: #65706c;
  --line: #d8ddda;
  --accent: #557b70;
  --sans: Inter, "Helvetica Neue", Arial, "Noto Sans SC", "PingFang SC", sans-serif;
  --serif: "Iowan Old Style", Baskerville, "Times New Roman", "Noto Serif SC", serif;
  --shell: min(1120px, calc(100vw - 56px));
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 82px; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 15px/1.62 var(--sans); text-rendering: optimizeLegibility; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 4px; }
a:hover { color: var(--accent); }
button { color: inherit; font: inherit; }
.shell { width: var(--shell); margin-inline: auto; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; top: 10px; left: 10px; z-index: 100; padding: 8px 12px; background: var(--ink); color: white; transform: translateY(-150%); }
.skip-link:focus { transform: none; }

.site-header { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid transparent; background: rgba(247, 248, 245, .95); backdrop-filter: blur(10px); transition: border-color .2s ease; }
.site-header.scrolled { border-color: var(--line); }
.nav-shell { height: 64px; display: flex; align-items: center; }
.wordmark { display: inline-flex; gap: .55rem; align-items: baseline; text-decoration: none; font-size: .88rem; letter-spacing: .02em; }
.wordmark-cn { font: 600 1.1rem var(--serif); }
.wordmark-separator { color: var(--line); }
.site-nav { display: flex; gap: 1.7rem; margin-left: auto; }
.site-nav a { text-decoration: none; color: var(--muted); font-size: .77rem; letter-spacing: .04em; }
.site-nav a:hover { color: var(--ink); }
.language-toggle { margin-left: 2rem; padding: 0; border: 0; background: none; cursor: pointer; color: var(--muted); font-size: .72rem; letter-spacing: .04em; }
[data-lang="zh"] .lang-zh, [data-lang="en"] .lang-en { color: var(--ink); font-weight: 700; }
.menu-toggle { display: none; }

.eyebrow, .section-index, .project-label { margin: 0; color: var(--accent); font-size: .7rem; font-weight: 650; letter-spacing: .12em; text-transform: uppercase; }
.hero { padding-block: clamp(50px, 6.5vw, 72px) 26px; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(320px, .75fr); gap: clamp(40px, 6vw, 68px); align-items: end; margin-top: 18px; }
.hero h1 { margin: 0; font: 400 clamp(3.25rem, 6.5vw, 5.2rem)/.94 var(--serif); letter-spacing: -.045em; }
.hero-name-en { display: block; margin-top: .22em; color: var(--muted); font: 400 clamp(1.15rem, 1.7vw, 1.55rem)/1.2 var(--sans); letter-spacing: .025em; }
.hero-role { margin: 15px 0 0; color: var(--muted); font-size: .85rem; }
.hero-statement > p { margin: 0; max-width: 500px; font: 400 clamp(1.35rem, 2.2vw, 1.75rem)/1.35 var(--serif); letter-spacing: -.018em; }
.hero-links { display: flex; flex-wrap: wrap; gap: 22px; margin-top: 21px; }
.hero-links a { border-bottom: 1px solid var(--ink); text-decoration: none; font-size: .78rem; }
.hero-rule { position: relative; height: 1px; margin-top: clamp(30px, 4vw, 44px); background: var(--line); }
.hero-rule span { position: absolute; left: 0; width: 18%; height: 1px; background: var(--accent); }

.section { padding-block: clamp(46px, 5.2vw, 62px); border-top: 1px solid var(--line); }
.section-heading { display: grid; grid-template-columns: 62px 1fr; align-items: baseline; margin-bottom: clamp(27px, 3vw, 34px); }
.section-heading h2 { margin: 0; font: 400 clamp(1.85rem, 2.8vw, 2.4rem)/1 var(--serif); letter-spacing: -.03em; }
.section-content { margin-left: 62px; }
.about-grid { display: grid; grid-template-columns: 1.18fr .82fr; gap: clamp(38px, 6vw, 72px); align-items: start; }
.about-grid p { margin: 0; color: var(--muted); }
.lead { color: var(--ink) !important; font: 400 clamp(1.2rem, 1.9vw, 1.55rem)/1.45 var(--serif); letter-spacing: -.012em; }

.research-section, .projects-section { background: var(--white); }
.research-intro { width: min(760px, calc(100% - 62px)); margin-left: 62px; }
.research-list { margin: 40px 0 0 62px; border-top: 1px solid var(--ink); }
.research-item { display: grid; grid-template-columns: 56px minmax(220px, .8fr) 1.2fr; gap: 26px; padding: 22px 0; border-bottom: 1px solid var(--line); }
.research-number { color: var(--accent); font-size: .7rem; letter-spacing: .09em; }
.research-item h3 { margin: 0; font: 400 clamp(1.25rem, 1.7vw, 1.55rem)/1.35 var(--serif); }
.research-item p { margin: 0; color: var(--muted); }

.publication-block { margin-left: 62px; }
.publication-heading { display: flex; justify-content: space-between; gap: 32px; align-items: baseline; padding-bottom: 15px; border-bottom: 1px solid var(--ink); }
.publication-heading h3 { margin: 0; font-size: .9rem; font-weight: 650; }
.publication-heading p { margin: 0; color: var(--muted); font-size: .7rem; }
.publication-list { margin: 0; padding: 0; list-style: none; counter-reset: publication; }
.publication-item { counter-increment: publication; display: grid; grid-template-columns: 38px 1fr 125px; gap: 22px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.publication-item::before { content: counter(publication, decimal-leading-zero); padding-top: .2rem; color: var(--accent); font-size: .68rem; letter-spacing: .06em; }
.publication-title { margin: 0; font: 400 clamp(1.08rem, 1.6vw, 1.3rem)/1.42 var(--serif); }
.publication-title a { text-decoration: none; }
.publication-authors { margin: 6px 0 0; color: var(--muted); font-size: .76rem; line-height: 1.48; }
.publication-authors .self { color: var(--ink); font-weight: 650; }
.publication-meta { margin: 0; color: var(--muted); font-size: .72rem; text-align: right; line-height: 1.5; }
.publication-meta span { display: block; }
.latest-block { margin-top: 50px; }
.latest-list .publication-title { font-family: var(--sans); font-size: .92rem; font-weight: 520; }
.latest-list .publication-item { padding-block: 17px; }
.publication-source { margin: 22px 0 0 62px; color: var(--muted); font-size: .7rem; }

.project-layout { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(54px, 8vw, 100px); margin-left: 62px; }
.project-column > .project-label { padding-bottom: 14px; border-bottom: 1px solid var(--ink); }
.project, .patent { padding: 16px 0; border-bottom: 1px solid var(--line); }
.project h3, .patent h3 { margin: 0; font-size: .92rem; font-weight: 580; line-height: 1.5; }
.project p, .patent p { margin: 7px 0 0; color: var(--muted); font-size: .72rem; }
.patent-type { color: var(--accent) !important; font-size: .68rem !important; letter-spacing: .07em; text-transform: uppercase; }
.patent a { text-decoration: none; }

.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(54px, 8vw, 100px); margin-left: 62px; }
.contact-intro { margin: 0; max-width: 500px; font: 400 clamp(1.25rem, 2.1vw, 1.7rem)/1.48 var(--serif); }
.contact-list { margin: 0; }
.contact-list div { display: grid; grid-template-columns: 105px 1fr; gap: 18px; padding: 11px 0; border-bottom: 1px solid var(--line); }
.contact-list dt { color: var(--muted); font-size: .72rem; }
.contact-list dd { margin: 0; font-size: .8rem; }
.contact-list a { text-decoration: none; }

.site-footer { padding: 38px 0 24px; background: var(--ink); color: #e4e8e5; }
.services { display: flex; justify-content: space-between; gap: 36px; padding-bottom: 38px; border-bottom: 1px solid #3d4542; }
.services > p { margin: 0; color: #94a09b; font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; }
.services > div { display: flex; gap: 30px; }
.services a { text-decoration: none; font-size: .74rem; }
.services a span { margin-left: 8px; color: #94a09b; }
.footer-meta { display: flex; justify-content: space-between; padding-top: 22px; color: #94a09b; font-size: .68rem; }
.footer-meta p { margin: 0; }
.footer-meta a { text-decoration: none; }

@media (max-width: 860px) {
  :root { --shell: min(720px, calc(100% - 40px)); }
  .nav-shell { height: 60px; }
  .menu-toggle { display: inline-flex; flex-direction: column; gap: 5px; margin-left: auto; padding: 8px; border: 0; background: none; }
  .menu-line { width: 20px; height: 1px; background: currentColor; }
  .site-nav { position: absolute; top: 60px; left: 0; right: 0; display: none; flex-direction: column; gap: 0; padding: 10px 20px 18px; border-bottom: 1px solid var(--line); background: var(--paper); }
  .site-nav.open { display: flex; }
  .site-nav a { padding: 8px 0; }
  .language-toggle { margin-left: 12px; }
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .about-grid, .project-layout, .contact-grid { grid-template-columns: 1fr; gap: 34px; }
  .research-item { grid-template-columns: 42px 1fr; }
  .research-item p { grid-column: 2; }
}

@media (max-width: 600px) {
  :root { --shell: calc(100% - 30px); }
  body { font-size: 14px; }
  .wordmark-separator, .wordmark > span:last-child { display: none; }
  .hero { padding-top: 38px; }
  .hero h1 { font-size: 3.25rem; }
  .hero-statement > p { font-size: 1.35rem; }
  .section { padding-block: 42px; }
  .section-heading { grid-template-columns: 38px 1fr; margin-bottom: 28px; }
  .section-content, .research-intro, .research-list, .publication-block, .publication-source, .project-layout, .contact-grid { width: auto; margin-left: 0; }
  .research-list { margin-top: 32px; }
  .research-item { grid-template-columns: 28px 1fr; gap: 16px; padding-block: 22px; }
  .publication-heading { display: block; }
  .publication-heading p { margin-top: 6px; }
  .publication-item { grid-template-columns: 26px 1fr; gap: 10px; padding-block: 18px; }
  .publication-meta { grid-column: 2; display: flex; gap: 10px; text-align: left; }
  .publication-meta span { display: inline; }
  .latest-block { margin-top: 44px; }
  .contact-list div { grid-template-columns: 82px 1fr; }
  .services { display: block; }
  .services > div { flex-direction: column; gap: 12px; margin-top: 22px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}