/* E-Man Lab site stylesheet */
:root {
  --navy: #12315e;
  --navy-2: #0b2242;
  --blue: #1f5fb4;
  --gold: #c9a227;
  --ink: #1d2733;
  --muted: #5b6b7d;
  --line: #e3e9f0;
  --bg-alt: #f4f7fb;
  --radius: 10px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Segoe UI", "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  color: var(--ink); line-height: 1.65; background: #fff;
}
.wrap { max-width: 1140px; margin: 0 auto; padding: 0 24px; }
img { max-width: 100%; display: block; }
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }

/* header */
.site-header {
  position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.96);
  backdrop-filter: blur(8px); border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; gap: 28px; height: 68px; }
.brand { display: flex; align-items: baseline; gap: 10px; color: var(--navy); }
.brand:hover { text-decoration: none; }
.brand-mark {
  font-size: 26px; font-weight: 800; letter-spacing: .5px; color: var(--navy);
  border-bottom: 3px solid var(--gold); padding-bottom: 1px;
}
.brand-sub { font-size: 13px; color: var(--muted); white-space: nowrap; }
.main-nav { display: flex; gap: 4px; margin-left: auto; }
.main-nav a {
  color: var(--ink); font-size: 15px; padding: 8px 12px; border-radius: 6px; white-space: nowrap;
}
.main-nav a:hover { background: var(--bg-alt); text-decoration: none; }
.main-nav a.active { color: var(--blue); font-weight: 600; }
.header-tools { display: flex; align-items: center; gap: 10px; }
.lang-switch {
  border: 1px solid var(--line); border-radius: 6px; padding: 5px 12px;
  font-size: 13px; color: var(--navy); font-weight: 600;
}
.lang-switch:hover { background: var(--navy); color: #fff; text-decoration: none; }
.nav-toggle { display: none; font-size: 22px; background: none; border: none; color: var(--navy); cursor: pointer; }

/* hero */
.hero {
  background: linear-gradient(135deg, var(--navy-2) 0%, var(--navy) 55%, #1d4f96 100%);
  color: #fff; padding: 96px 0 88px; position: relative; overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; right: -140px; top: -140px; width: 480px; height: 480px;
  border-radius: 50%; background: radial-gradient(circle, rgba(201,162,39,.28), transparent 65%);
}
.hero-kicker { color: #9fb8dd; font-size: 15px; letter-spacing: 1px; margin-bottom: 14px; }
.hero-title { font-size: 56px; font-weight: 800; letter-spacing: 1px; line-height: 1.15; }
.hero-amp { color: var(--gold); }
.hero-tagline { margin-top: 18px; font-size: 19px; color: #d5e2f2; max-width: 760px; }
.hero-cta { margin-top: 34px; display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  display: inline-block; background: var(--gold); color: #1c2431; font-weight: 700;
  padding: 12px 26px; border-radius: 8px; font-size: 16px;
}
.btn:hover { background: #d9b845; text-decoration: none; }
.btn-ghost { background: transparent; color: #fff; border: 2px solid rgba(255,255,255,.55); }
.btn-ghost:hover { background: rgba(255,255,255,.12); }

/* sections */
.section { padding: 64px 0; }
.section-alt { background: var(--bg-alt); }
.sec-title {
  font-size: 28px; color: var(--navy); margin-bottom: 26px; position: relative; padding-bottom: 10px;
}
.sec-title::after { content: ""; position: absolute; left: 0; bottom: 0; width: 54px; height: 3px; background: var(--gold); }
.rich p { margin: 0 0 14px; }
.rich ul, .rich ol { margin: 0 0 14px 22px; }
.rich h2, .rich h3 { color: var(--navy); margin: 26px 0 10px; }
.rich strong { color: var(--navy); }

/* about */
.about-grid { display: grid; grid-template-columns: 1.6fr 1fr; gap: 44px; align-items: start; }
.about-fig img { border-radius: var(--radius); box-shadow: 0 8px 28px rgba(18,49,94,.16); }
.about-fig figcaption { margin-top: 10px; font-size: 13px; color: var(--muted); text-align: center; }
.stats { display: flex; gap: 36px; margin-top: 26px; flex-wrap: wrap; }
.stat-n { font-size: 34px; font-weight: 800; color: var(--navy); }
.stat-l { font-size: 13px; color: var(--muted); }

/* cards */
.card-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 26px; }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden;
  color: var(--ink); transition: box-shadow .2s, transform .2s; display: block;
}
.card:hover { box-shadow: 0 12px 30px rgba(18,49,94,.14); transform: translateY(-3px); text-decoration: none; }
.card-img { aspect-ratio: 16/7.5; overflow: hidden; background: #e8edf4; }
.card-img img { width: 100%; height: 100%; object-fit: cover; }
.card-body { padding: 18px 20px 22px; }
.card-body h3 { color: var(--navy); font-size: 18px; margin-bottom: 8px; }
.card-body p { font-size: 14px; color: var(--muted); }

/* home columns */
.home-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.news-row { display: flex; gap: 14px; padding: 12px 0; border-bottom: 1px solid var(--line); color: var(--ink); align-items: baseline; }
.news-row:hover .news-title { color: var(--blue); }
.news-row:hover { text-decoration: none; }
.news-date { color: var(--muted); font-size: 13px; white-space: nowrap; font-variant-numeric: tabular-nums; }
.news-title { font-size: 15px; font-weight: 600; }
.pub-row { padding: 10px 0; border-bottom: 1px solid var(--line); }
.pub-title { font-weight: 600; font-size: 15px; }
.pub-meta { font-size: 13.5px; color: var(--muted); margin-top: 3px; }
.more { display: inline-block; margin-top: 16px; font-weight: 600; }

/* page hero */
.page-hero { background: linear-gradient(120deg, var(--navy-2), var(--navy)); color: #fff; padding: 56px 0; }
.page-hero h1 { font-size: 36px; }
.page-hero p { margin-top: 10px; color: #c8d8ee; max-width: 800px; }

/* research blocks */
.research-block {
  display: grid; grid-template-columns: 1.05fr 1fr; gap: 40px; align-items: center;
  padding: 42px 0; border-bottom: 1px solid var(--line);
}
.research-block:last-child { border-bottom: none; }
.research-block.flip .research-img { order: 2; }
.research-img img { border-radius: var(--radius); box-shadow: 0 10px 26px rgba(18,49,94,.14); }
.research-num { font-size: 44px; font-weight: 800; color: #dfe7f2; line-height: 1; }
.research-txt h2 { color: var(--navy); font-size: 24px; margin: 6px 0 8px; }
.research-tag { color: var(--blue); font-weight: 600; margin-bottom: 14px; }

/* publications */
.year-h {
  font-size: 22px; color: var(--navy); margin: 34px 0 14px; padding-bottom: 8px; border-bottom: 2px solid var(--gold);
  display: inline-block;
}
.pub-note { color: var(--muted); margin-bottom: 8px; }
.pub-item { padding: 14px 0 14px 18px; border-left: 3px solid var(--line); margin-bottom: 6px; }
.pub-item.pub-hl { border-left-color: var(--gold); background: #fffdf5; }
.pub-item .pub-authors { font-size: 13.5px; color: var(--muted); margin-top: 4px; }
.pub-item .pub-meta { margin-top: 3px; }
.badge { color: var(--gold); }
.pub-note-item { font-size: 13px; color: var(--blue); margin-top: 4px; }

/* news */
.news-item {
  display: flex; gap: 22px; padding: 20px 0; border-bottom: 1px solid var(--line); color: var(--ink);
}
.news-item:hover { text-decoration: none; }
.news-item:hover h3 { color: var(--blue); }
.news-thumb { width: 200px; flex-shrink: 0; }
.news-thumb img { border-radius: 8px; aspect-ratio: 16/10; object-fit: cover; }
.news-item h3 { color: var(--navy); font-size: 18px; margin: 4px 0 8px; }
.news-item p { color: var(--muted); font-size: 14.5px; }
.article { max-width: 800px; }
.article h1 { color: var(--navy); font-size: 30px; margin: 10px 0 6px; }
.article-img { border-radius: var(--radius); margin: 22px 0; }

/* members */
.member-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; margin-bottom: 12px; }
.pi-grid { grid-template-columns: 1fr; max-width: 560px; }
.member-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 18px; text-align: center;
}
.pi-card { display: grid; grid-template-columns: 180px 1fr; text-align: left; gap: 22px; align-items: center; }
.pi-card .member-photo { width: 180px; height: 220px; }
.pi-card h3 { font-size: 22px; }
.member-photo {
  width: 110px; height: 132px; margin: 0 auto 12px; border-radius: 8px; overflow: hidden;
  background: var(--bg-alt); display: flex; align-items: center; justify-content: center;
}
.member-photo img { width: 100%; height: 100%; object-fit: cover; }
.member-photo span { font-size: 40px; color: #b9c7d8; font-weight: 800; }
.member-card h3 { color: var(--navy); font-size: 17px; }
.member-role { color: var(--blue); font-size: 13.5px; font-weight: 600; margin: 4px 0 6px; }
.member-card p { font-size: 13px; color: var(--muted); }
.member-links { margin-top: 8px; font-size: 13px; display: flex; gap: 10px; justify-content: center; }
.pi-card .member-links { justify-content: flex-start; }

/* contact */
.contact-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-top: 30px; }
.contact-card { border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; }
.contact-card h3 { color: var(--navy); margin-bottom: 8px; font-size: 16px; }

/* footer */
.site-footer { background: var(--navy-2); color: #b8c9e0; margin-top: 20px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 36px; padding: 48px 24px 30px; }
.footer-brand { font-size: 18px; font-weight: 700; color: #fff; margin-bottom: 10px; }
.footer-h { color: #fff; font-weight: 700; margin-bottom: 10px; font-size: 15px; }
.site-footer a { color: #b8c9e0; display: block; padding: 3px 0; font-size: 14px; }
.site-footer a:hover { color: #fff; }
.footer-addr { font-size: 13.5px; }
.footer-copy { border-top: 1px solid rgba(255,255,255,.12); padding: 16px 24px 22px; font-size: 13px; }

/* responsive */
@media (max-width: 900px) {
  .about-grid, .home-cols, .research-block, .contact-cards { grid-template-columns: 1fr; }
  .research-block.flip .research-img { order: 0; }
  .card-grid { grid-template-columns: 1fr; }
  .member-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-title { font-size: 40px; }
  .pi-card { grid-template-columns: 1fr; text-align: center; }
  .pi-card .member-photo { margin: 0 auto 12px; }
  .pi-card .member-links { justify-content: center; }
}
@media (max-width: 760px) {
  .main-nav {
    display: none; position: absolute; top: 68px; left: 0; right: 0; background: #fff;
    flex-direction: column; padding: 12px; border-bottom: 1px solid var(--line);
  }
  .main-nav.open { display: flex; }
  .nav-toggle { display: block; }
  .brand-sub { display: none; }
  .header-inner { gap: 12px; }
  .main-nav { margin-left: 0; }
  .header-tools { margin-left: auto; }
}

/* ---- bilingual (zh + en on same page) ---- */
.l-en { color: var(--muted); font-size: .93em; }
.rich.l-en { border-top: 1px dashed var(--line); padding-top: 12px; margin-top: 12px; }
.l-en-f { opacity: .78; font-size: .92em; font-weight: 400; }
.nav-en { display: block; font-size: 11px; color: var(--muted); font-weight: 400; line-height: 1.2; }
.main-nav a { line-height: 1.25; padding: 6px 12px; text-align: center; }
.brand-sub { line-height: 1.3; }
.brand-sub-en { font-size: 11px; color: #9fb0c7; }
.hero-kicker { line-height: 1.5; }
.hero-kicker-en { font-size: 13.5px; }
.hero-tagline-en { color: #a9bedd; font-size: 16.5px; margin-top: 8px; }
.ph-en { font-size: .55em; color: #9fb8dd; font-weight: 600; }
.card-en { font-size: 14px; font-weight: 600; margin: 2px 0 6px; }
.research-h-en { font-size: 17px; font-weight: 600; margin-top: -4px; }
.news-title-en { display: block; font-size: 13px; color: var(--muted); font-weight: 500; }
.news-h-en { font-size: 14.5px; font-weight: 600; margin-top: -4px; }
.article-h-en { font-size: 20px; font-weight: 600; margin-top: 2px; }
.member-name-en { display: block; font-size: 13px; color: var(--muted); font-weight: 500; }
.member-role .l-en-f { display: block; font-size: 12px; }
.stat-l .l-en-f { font-size: 12px; }
.pub-note-item .l-en { font-size: inherit; }
.lang-switch { display: none; }