:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --text: #172033;
  --muted: #5f6b7a;
  --line: #dfe5ec;
  --accent: #184f90;
  --accent-soft: #eaf2fb;
  --max-width: 1060px;
}

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

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

.container { width: min(calc(100% - 40px), var(--max-width)); margin: 0 auto; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid rgba(223, 229, 236, .9);
  background: rgba(248, 250, 252, .92);
  backdrop-filter: blur(14px);
}

.nav-wrap {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}
.brand {
  color: var(--text);
  font-weight: 760;
  letter-spacing: -.02em;
  font-size: 1.06rem;
}
.optim-link {
  color: #d97706;
  /* font-weight: 600; */
}

.brand:hover { text-decoration: none; }
nav { display: flex; gap: 24px; }
nav a { color: var(--muted); font-size: .95rem; font-weight: 560; }
nav a:hover { color: var(--text); text-decoration: none; }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 270px;
  gap: 72px;
  align-items: center;
  min-height: 620px;
  padding-top: 80px;
  padding-bottom: 80px;
}
.eyebrow, .section-kicker {
  margin: 0 0 10px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .12em;
  font-size: .76rem;
  font-weight: 780;
}
h1 {
  margin: 0 0 24px;
  font-size: clamp(3rem, 8vw, 5.8rem);
  line-height: .98;
  letter-spacing: -.06em;
}
.lead { margin: 0; max-width: 760px; font-size: 1.13rem; color: #354052; }
.links { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 28px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text);
  font-size: .91rem;
  font-weight: 650;
}
.button:hover { border-color: #b6c0cc; text-decoration: none; }
.button.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.contact-card {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 20px;
  font-size: .92rem;
  color: var(--muted);
}
.contact-label { font-weight: 720; color: var(--text); }
.dot { color: #a1a9b3; }
.portrait-wrap { display: flex; justify-content: center; }
.portrait {
  width: 250px;
  height: 250px;
  object-fit: cover;
  border-radius: 26px;
  background: var(--accent-soft);
  box-shadow: 0 18px 60px rgba(23, 32, 51, .13);
}

.section { padding: 92px 0; border-top: 1px solid var(--line); }
.section-heading { margin-bottom: 38px; }
h2 { margin: 0; font-size: clamp(2rem, 5vw, 3.1rem); letter-spacing: -.04em; line-height: 1.08; }
h3 { margin: 0 0 5px; font-size: 1.06rem; }
p { margin-top: 0; }
.section-intro { max-width: 760px; color: var(--muted); font-size: 1.06rem; margin-bottom: 34px; }
.timeline { display: grid; gap: 0; }
.timeline-item {
  display: grid;
  grid-template-columns: 190px 1fr;
  gap: 28px;
  padding: 26px 0;
  border-top: 1px solid var(--line);
}
.timeline-item:last-child { border-bottom: 1px solid var(--line); }
.date { color: var(--muted); font-size: .94rem; font-variant-numeric: tabular-nums; }
.timeline-item p { margin: 0; color: var(--muted); }
.research-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.research-card {
  min-height: 190px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
}
.research-card span { display: block; margin-bottom: 34px; color: #8d99a8; font-size: .78rem; font-weight: 750; letter-spacing: .08em; }
.research-card p { margin: 0; color: var(--muted); font-size: .95rem; }
.site-footer { border-top: 1px solid var(--line); padding: 30px 0 44px; }
.footer-wrap { display: flex; justify-content: space-between; gap: 24px; color: var(--muted); font-size: .88rem; }
.footer-wrap p { margin: 0; }

@media (max-width: 760px) {
  .nav-wrap { min-height: 60px; }
  nav { gap: 14px; }
  nav a { font-size: .86rem; }
  .hero { grid-template-columns: 1fr; gap: 38px; min-height: auto; padding-top: 62px; }
  .portrait-wrap { justify-content: flex-start; order: -1; }
  .portrait { width: 150px; height: 150px; border-radius: 20px; }
  .timeline-item { grid-template-columns: 1fr; gap: 7px; }
  .research-grid { grid-template-columns: 1fr; }
  .footer-wrap { flex-direction: column; gap: 6px; }
}

@media (max-width: 500px) {
  .container { width: min(calc(100% - 28px), var(--max-width)); }
  .brand { display: none; }
  .nav-wrap { justify-content: center; }
  nav { width: 100%; justify-content: space-between; }
  .hero { padding-top: 48px; padding-bottom: 64px; }
  .section { padding: 68px 0; }
}

/* Multi-page academic content */
nav a.active { color: var(--text); font-weight: 720; }
.page-main { min-height: 72vh; }
.page-hero { padding-top: 92px; padding-bottom: 56px; }
.page-title { font-size: clamp(3.2rem, 8vw, 6.4rem); margin-bottom: 20px; }
.page-lead { max-width: 700px; color: var(--muted); font-size: 1.08rem; }
.section-heading.compact { margin-bottom: 26px; }
.notation { margin: 10px 0 0; color: var(--muted); font-size: .88rem; }

.publication-list, .progress-list, .experience-list, .award-list { display: grid; }
.publication-item {
  padding: 30px 0;
  border-top: 1px solid var(--line);
}
.publication-item:last-child { border-bottom: 1px solid var(--line); }
.pub-meta { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 12px; }
.venue-badge, .status-badge, .work-status, .tag {
  display: inline-flex;
  width: fit-content;
  align-items: center;
  border-radius: 6px;
  padding: 4px 8px;
  font-size: .75rem;
  font-weight: 760;
  letter-spacing: .035em;
  text-transform: uppercase;
}
.venue-badge { background: #edf1e8; color: #3f5544; }
.status-badge { background: var(--accent-soft); color: var(--accent); }
.publication-item h3 { max-width: 920px; font-size: 1.15rem; line-height: 1.45; margin-bottom: 10px; }
.publication-item h3 a { color: var(--text); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; }
.publication-item h3 a:hover { color: var(--accent); }
.authors { margin: 0 0 7px; color: #354052; }
.pub-venue { margin: 0; color: var(--muted); }
.pub-links { display: flex; gap: 10px; margin-top: 14px; }
.pub-links a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  color: var(--accent);
  font-size: .82rem;
  font-weight: 700;
}
.pub-links a:hover { text-decoration: none; border-color: #b8c2ce; }

.progress-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 7px 18px;
  align-items: start;
  padding: 23px 0;
  border-top: 1px solid var(--line);
}
.progress-item:last-child { border-bottom: 1px solid var(--line); }
.progress-item h3 { font-size: 1.04rem; line-height: 1.5; }
.progress-item p { grid-column: 1 / -1; margin: 0; color: var(--muted); }
.work-status { background: #eef2f6; color: #5b6675; white-space: nowrap; }

.experience-item {
  padding: 26px 0;
  border-top: 1px solid var(--line);
}
.experience-item:last-child { border-bottom: 1px solid var(--line); }
.experience-tags { display: flex; gap: 7px; margin-bottom: 10px; }
.tag { background: #eef2f6; color: #596674; }
.tag.oral { background: #e6f4ea; color: #346445; }
.experience-item h3 { font-size: 1.08rem; line-height: 1.45; margin-bottom: 7px; }
.experience-item p { margin: 0; color: var(--muted); }
.experience-meta { margin-top: 4px !important; font-size: .92rem; }

.project-list { display: grid; }
.project-item {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 28px;
  padding: 26px 0;
  border-top: 1px solid var(--line);
}
.project-item:last-child { border-bottom: 1px solid var(--line); }
.project-period { color: var(--muted); font-size: .91rem; font-variant-numeric: tabular-nums; }
.project-item h3 { line-height: 1.5; }
.project-item p { margin: 7px 0 0; color: var(--muted); }

.award-item {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 22px;
  padding: 19px 0;
  border-top: 1px solid var(--line);
}
.award-item:last-child { border-bottom: 1px solid var(--line); }
.award-year { color: var(--accent); font-weight: 780; font-variant-numeric: tabular-nums; }
.award-item p { margin: 0; color: #354052; }

@media (max-width: 760px) {
  .page-hero { padding-top: 64px; padding-bottom: 40px; }
  .project-item { grid-template-columns: 1fr; gap: 7px; }
  .progress-item { grid-template-columns: 1fr; }
  .progress-item p { grid-column: 1; }
}

@media (max-width: 500px) {
  .award-item { grid-template-columns: 1fr; gap: 4px; }
  .pub-links { flex-wrap: wrap; }
}