:root {
  --bg: #ffffff; --bg-soft: #f6f6f4; --text: #1d1d1f; --muted: #5d5d63; --line: #e3e3e0;
  --accent: #c8102e; --accent-ink: #a50d26; --card: #ffffff; --shadow: 0 1px 2px rgba(0,0,0,.05), 0 4px 16px rgba(0,0,0,.05);
  --serif: "Source Serif 4", Georgia, serif; --sans: Inter, system-ui, -apple-system, "Segoe UI", sans-serif;
  --maxw: 1080px;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #121214; --bg-soft: #1b1b1e; --text: #ececee; --muted: #a3a3aa; --line: #2c2c31;
          --accent: #ff4d63; --accent-ink: #ff7385; --card: #18181b; --shadow: none; }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 16px/1.65 var(--sans); }
a { color: var(--accent-ink); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
main.wrap { padding-top: 32px; padding-bottom: 64px; min-height: 60vh; }
h1, h2, h3 { line-height: 1.25; }
h1 { font: 600 2.1rem/1.2 var(--serif); margin: .2em 0 .5em; letter-spacing: -.01em; }
h2 { font: 600 1.45rem/1.3 var(--serif); margin: 1.8em 0 .6em; }
h3 { font-size: 1.05rem; margin: 0 0 .35em; }
.lede { font-size: 1.08rem; color: var(--muted); max-width: 46rem; }

/* header */
.site-header { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: saturate(1.4) blur(8px); border-bottom: 1px solid var(--line); }
.header-inner { display: flex; align-items: center; gap: 24px; min-height: 64px; }
.brand { display: flex; flex-direction: column; line-height: 1.1; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand-name { font: 700 1.15rem var(--serif); }
.brand-sub { font-size: .75rem; color: var(--muted); letter-spacing: .02em; }
.site-nav { margin-left: auto; display: flex; gap: 4px; flex-wrap: wrap; }
.site-nav a { color: var(--text); padding: 6px 10px; border-radius: 8px; font-size: .94rem; font-weight: 500; }
.site-nav a:hover { background: var(--bg-soft); text-decoration: none; }
.site-nav a[aria-current="page"] { color: var(--accent-ink); background: color-mix(in srgb, var(--accent) 9%, transparent); }
.nav-toggle { display: none; margin-left: auto; background: none; border: 1px solid var(--line); color: var(--text);
  border-radius: 8px; font-size: 1.2rem; padding: 4px 10px; cursor: pointer; }

/* hero */
.hero { display: grid; grid-template-columns: 1fr 240px; gap: 48px; align-items: center; padding: 24px 0 8px; }
.eyebrow { text-transform: uppercase; letter-spacing: .08em; font-size: .78rem; color: var(--accent-ink); font-weight: 600; margin: 0; }
.hero h1 { font-size: 2.5rem; margin-top: .3em; }
.cta { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 1.4em; }
.btn { display: inline-block; padding: 10px 18px; border-radius: 10px; background: var(--accent); color: #fff; font-weight: 600; }
.btn:hover { text-decoration: none; filter: brightness(1.05); }
.btn.ghost { background: transparent; color: var(--accent-ink); border: 1px solid color-mix(in srgb, var(--accent) 40%, transparent); }
.pi { margin: 0; text-align: center; }
.pi img { width: 200px; height: 200px; object-fit: cover; border-radius: 50%; box-shadow: var(--shadow); }
.pi figcaption { color: var(--muted); font-size: .9rem; margin-top: 10px; }

/* research cards */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 16px; }
.card { display: block; padding: 18px 20px; border: 1px solid var(--line); border-radius: 14px; background: var(--card);
  color: var(--text); box-shadow: var(--shadow); transition: border-color .15s, transform .15s; }
.card:hover { text-decoration: none; border-color: color-mix(in srgb, var(--accent) 45%, var(--line)); transform: translateY(-2px); }
.card h3 { color: var(--accent-ink); }
.card p { margin: 0; color: var(--muted); font-size: .95rem; }
.two-col { display: grid; grid-template-columns: 1.1fr 1fr; gap: 48px; }

/* news */
.news { list-style: none; padding: 0; margin: 0; }
.news li { display: grid; grid-template-columns: 82px 1fr; gap: 14px; padding: 10px 0; border-bottom: 1px solid var(--line); }
.news time { color: var(--muted); font-size: .88rem; font-variant-numeric: tabular-nums; padding-top: 2px; }

/* prose */
.prose { max-width: 50rem; }
.prose h2 { border-top: 1px solid var(--line); padding-top: 1.2em; }
.prose h2:first-child { border-top: 0; padding-top: 0; margin-top: .4em; }
.prose li { margin: .35em 0; }

/* people */
.pi-block { display: grid; grid-template-columns: 180px 1fr; gap: 32px; align-items: start; }
.pi-block img { width: 180px; height: 180px; object-fit: cover; border-radius: 50%; }
.pi-block h2 { margin-top: 0; }
.links { font-size: .95rem; }
.people { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 18px 20px; }
.person { display: flex; gap: 14px; align-items: center; }
.person img, .avatar { width: 76px; height: 76px; border-radius: 50%; object-fit: cover; flex: none; }
.avatar { display: grid; place-items: center; background: var(--bg-soft); color: var(--muted); font-weight: 600; border: 1px solid var(--line); }
.alumni .person img, .alumni .avatar { width: 60px; height: 60px; }
.pname { font-weight: 600; }
.prole, .now { color: var(--muted); font-size: .88rem; line-height: 1.4; }
.group-photo { margin: 40px 0 0; }
.group-photo img { border-radius: 14px; }
.group-photo figcaption { color: var(--muted); font-size: .88rem; margin-top: 6px; }

/* publications */
.year { font-family: var(--sans); font-size: 1.05rem; color: var(--accent-ink); border-bottom: 1px solid var(--line); padding-bottom: 4px; }
.pubs { padding-left: 1.4em; margin: 0; }
.pubs li { margin: .6em 0; font-size: .95rem; }
.doi { font-size: .82rem; border: 1px solid var(--line); border-radius: 6px; padding: 0 6px; margin-left: 4px; white-space: nowrap; }

/* code */
.repos { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }
.repo { padding: 16px 18px; border: 1px solid var(--line); border-radius: 14px; background: var(--card); }
.repo p { margin: .3em 0; color: var(--muted); font-size: .94rem; }
.repo .paper { font-size: .86rem; }

/* footer */
.site-footer { border-top: 1px solid var(--line); background: var(--bg-soft); color: var(--muted); font-size: .9rem; }
.footer-inner { display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap; padding: 28px 20px; }
.footer-links { display: flex; gap: 16px; flex-wrap: wrap; align-items: flex-start; }

/* mobile */
@media (max-width: 820px) {
  .nav-toggle { display: block; }
  .site-nav { display: none; position: absolute; top: 64px; left: 0; right: 0; flex-direction: column;
    background: var(--bg); border-bottom: 1px solid var(--line); padding: 8px 16px 16px; }
  .nav-open .site-nav { display: flex; }
  .hero { grid-template-columns: 1fr; gap: 24px; }
  .hero h1 { font-size: 1.9rem; }
  .pi { order: -1; text-align: left; display: flex; align-items: center; gap: 16px; }
  .pi img { width: 96px; height: 96px; }
  .pi figcaption { margin: 0; text-align: left; }
  .two-col { grid-template-columns: 1fr; gap: 8px; }
  .pi-block { grid-template-columns: 1fr; }
  .pi-block img { width: 120px; height: 120px; }
  .wrap { padding: 0 16px; }
  h1 { font-size: 1.75rem; }
}

/* resources */
.prose a.btn { color: #fff; margin: .4em 0 .6em; }
.prose a.btn:hover { text-decoration: none; }
.prose h3 { font-size: 1.15rem; margin-top: 1.2em; }
.prose table { border-collapse: collapse; width: 100%; font-size: .9rem; margin: .8em 0; display: block; overflow-x: auto; }
.prose th, .prose td { border-bottom: 1px solid var(--line); padding: 6px 10px; text-align: left; vertical-align: top; }
.prose th { color: var(--muted); font-weight: 600; }