:root {
  --primary: #1f4e79;
  --primary-dark: #143656;
  --accent: #c9a227;
  --text: #1f2937;
  --muted: #6b7280;
  --bg: #ffffff;
  --bg-alt: #f7f8fa;
  --border: #e5e7eb;
  --max-w: 1080px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header / Nav */
.site-header {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--primary-dark);
}
.nav a {
  margin-left: 24px;
  color: var(--text);
  font-weight: 500;
  padding-bottom: 4px;
  border-bottom: 2px solid transparent;
}
.nav a:hover { color: var(--primary); text-decoration: none; }
.nav a.active {
  color: var(--primary);
  border-bottom-color: var(--accent);
}
.nav-toggle {
  display: none;
  background: none; border: none; font-size: 1.4rem; cursor: pointer;
}

/* Sub-nav (Academic page anchors) */
.sub-nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin: 8px 0 12px;
  padding: 10px 12px;
  background: var(--bg-alt);
  border-radius: 8px;
  border: 1px solid var(--border);
}
.sub-nav a {
  padding: 6px 14px;
  border-radius: 20px;
  background: #fff;
  border: 1px solid var(--border);
  color: var(--primary);
  font-weight: 500;
  font-size: 0.9rem;
}
.sub-nav a:hover {
  background: var(--primary);
  color: #fff;
  text-decoration: none;
}

/* Hero */
.hero {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 36px;
  align-items: center;
  padding: 48px 0 24px;
}
.hero-photo img {
  width: 220px;
  height: 220px;
  object-fit: cover;
  border-radius: 50%;
  border: 4px solid var(--bg-alt);
  box-shadow: 0 6px 20px rgba(0,0,0,0.08);
}
.hero-text h1 {
  margin: 0 0 6px;
  font-size: 2rem;
  color: var(--primary-dark);
}
.hero-text .title { margin: 0; color: var(--muted); }
.hero-text .affiliation { margin: 4px 0 16px; font-weight: 500; }

.fellow-badge {
  display: inline-block;
  margin: 10px 0;
  padding: 6px 14px;
  background: linear-gradient(135deg, #fdf3d3 0%, #f5e6a8 100%);
  color: #7a5a00;
  border: 1px solid #e6cf7a;
  border-radius: 24px;
  font-weight: 600;
  font-size: 0.92rem;
  letter-spacing: 0.2px;
}

.quick-links { list-style: none; padding: 0; margin: 0; }
.quick-links li { margin: 4px 0; }

/* Sections */
.section { padding: 28px 0; border-top: 1px solid var(--border); }
.section h2 {
  color: var(--primary-dark);
  font-size: 1.4rem;
  margin: 0 0 14px;
}
.sub-h {
  color: var(--primary);
  font-size: 1.1rem;
  margin: 22px 0 10px;
  padding-bottom: 6px;
  border-bottom: 1px dashed var(--border);
}
h1 { color: var(--primary-dark); margin-top: 28px; }

/* Cards */
.cards {
  list-style: none; padding: 0; margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}
.card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 18px;
  transition: transform .2s, box-shadow .2s;
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 22px rgba(0,0,0,0.07);
}
.card h3 {
  margin: 0 0 6px;
  color: var(--primary);
  font-size: 1.05rem;
}
.card p { margin: 0; color: var(--muted); }

/* Bullets / Timeline */
.bullets { padding-left: 22px; }
.bullets li { margin: 6px 0; }
.timeline {
  list-style: none;
  padding: 0;
  border-left: 2px solid var(--border);
}
.timeline li {
  padding: 8px 0 8px 18px;
  position: relative;
}
.timeline li::before {
  content: "";
  width: 10px; height: 10px;
  background: var(--accent);
  border-radius: 50%;
  position: absolute;
  left: -6px; top: 14px;
}

/* Publications */
.pub-list { padding-left: 22px; }
.pub-list li { margin: 10px 0; }

/* Topics */
.topic { padding: 16px 0; border-bottom: 1px dashed var(--border); }
.topic:last-child { border-bottom: none; }
.topic h3 { color: var(--primary); margin: 0 0 6px; }

/* Contact */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
}
.contact-grid h3 {
  color: var(--primary);
  margin: 14px 0 4px;
  font-size: 1rem;
}

/* Map */
.map-wrap {
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  background: var(--bg-alt);
}
.map-wrap iframe {
  width: 100%;
  height: 420px;
  border: 0;
  display: block;
}
.map-link {
  margin: 0;
  padding: 10px 14px;
  background: #fff;
  border-top: 1px solid var(--border);
  font-size: 0.9rem;
  text-align: right;
}

/* Footer */
.site-footer {
  margin-top: 60px;
  padding: 24px 0;
  background: var(--bg-alt);
  color: var(--muted);
  text-align: center;
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
  .nav { display: none; position: absolute; top: 64px; left: 0; right: 0;
         background: #fff; border-bottom: 1px solid var(--border);
         padding: 12px 24px; flex-direction: column; }
  .nav.open { display: flex; }
  .nav a { margin: 8px 0; }
  .nav-toggle { display: block; }
  .hero { grid-template-columns: 1fr; text-align: center; padding-top: 30px; }
  .hero-photo img { margin: 0 auto; width: 180px; height: 180px; }
  .quick-links { display: inline-block; text-align: left; }
  .contact-grid { grid-template-columns: 1fr; }
  .map-wrap iframe { height: 320px; }
}