:root {
  --bg: #f7f8fb;
  --text: #162033;
  --muted: #5b667a;
  --line: #dbe1ea;
  --card: #ffffff;
  --accent: #1f5eff;
  --accent-dark: #113fb4;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
.container { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.site-header { position: sticky; top: 0; z-index: 10; background: rgba(247,248,251,.9); backdrop-filter: blur(14px); border-bottom: 1px solid var(--line); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { font-weight: 800; letter-spacing: -0.03em; font-size: 1.2rem; }
.nav-links { display: flex; gap: 22px; color: var(--muted); font-size: .95rem; }
.nav-links a:hover { color: var(--accent); }
.hero { display: grid; grid-template-columns: 1.6fr .9fr; gap: 48px; align-items: center; padding: 92px 0 64px; }
.eyebrow { margin: 0 0 12px; text-transform: uppercase; letter-spacing: .12em; font-size: .78rem; font-weight: 800; color: var(--accent); }
h1 { margin: 0; font-size: clamp(2.6rem, 6vw, 5.3rem); line-height: .96; letter-spacing: -0.07em; max-width: 860px; }
h2 { margin: 0; font-size: clamp(1.8rem, 3vw, 2.8rem); line-height: 1.1; letter-spacing: -0.04em; }
h3 { margin: 0 0 10px; font-size: 1.15rem; }
p { color: var(--muted); }
.hero-text { margin: 26px 0 32px; font-size: 1.18rem; max-width: 760px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.button { display: inline-flex; align-items: center; border-radius: 999px; padding: 12px 18px; font-weight: 700; border: 1px solid var(--line); }
.button.primary { color: white; background: var(--accent); border-color: var(--accent); }
.button.primary:hover { background: var(--accent-dark); }
.button.secondary { background: white; }
.button.secondary:hover { border-color: var(--accent); color: var(--accent); }
.hero-card, .card, .timeline-item, .skill-grid > div, .contact-section { background: var(--card); border: 1px solid var(--line); border-radius: 28px; box-shadow: 0 20px 60px rgba(21, 34, 66, .06); }
.hero-card { padding: 30px; }
.hero-card ul { padding-left: 18px; color: var(--muted); }
.section { padding: 70px 0; }
.section-heading { max-width: 740px; margin-bottom: 28px; }
.two-column { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; font-size: 1.05rem; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card { padding: 26px; }
.timeline { display: grid; gap: 16px; }
.timeline-item { padding: 26px; }
.meta { margin-top: -4px; font-size: .92rem; color: var(--accent-dark); font-weight: 700; }
.publications { background: var(--card); border: 1px solid var(--line); border-radius: 28px; padding: 28px; }
.publications p { margin: 0 0 22px; }
.publications p:last-child { margin-bottom: 0; }
.skill-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.skill-grid > div { padding: 24px; }
.contact-section { padding: 42px; text-align: center; }
.contact-section p { max-width: 760px; margin: 16px auto 24px; }
.contact-links { display: flex; justify-content: center; gap: 18px; flex-wrap: wrap; }
.contact-links a { color: var(--accent); font-weight: 800; }
.footer { padding: 32px 0 48px; border-top: 1px solid var(--line); }
.footer p { font-size: .9rem; }
@media (max-width: 850px) {
  .nav { align-items: flex-start; height: auto; padding: 18px 0; gap: 14px; flex-direction: column; }
  .nav-links { flex-wrap: wrap; gap: 14px; }
  .hero, .two-column, .cards, .skill-grid { grid-template-columns: 1fr; }
  .hero { padding-top: 58px; }
}