/* ── Variables ── */
:root {
  --cream: #faf8f4;
  --warm-white: #f5f2ec;
  --sand: #e8e0d4;
  --bark: #c4b49a;
  --brown: #7a6652;
  --dark: #2c2420;
  --text: #3d342c;
  --text-muted: #8a7a6e;
  --accent: #c17d5a;
  --accent-light: #f0e4d8;
  --teal: #4a8b8c;
  --teal-light: #e0f0f0;
  --radius: 12px;
  --radius-sm: 6px;
  --serif: 'Lora', Georgia, serif;
  --sans: 'DM Sans', system-ui, sans-serif;
  --transition: 0.25s ease;
  --shadow: 0 2px 16px rgba(44,36,32,0.07);
  --shadow-md: 0 4px 28px rgba(44,36,32,0.11);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--sans);
  background: var(--cream);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--brown); }

/* ── Nav ── */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250,248,244,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--sand);
}
.nav-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 2rem;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-family: var(--serif);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--dark);
  letter-spacing: -0.01em;
}
.nav-logo:hover { color: var(--accent); }
.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}
.nav-links a {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--text-muted);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  transition: color var(--transition);
}
.nav-links a:hover { color: var(--accent); }
.nav-toggle { display: none; background: none; border: none; font-size: 1.25rem; cursor: pointer; color: var(--text); }

/* ── Hero ── */
.hero {
  min-height: 92vh;
  display: flex;
  align-items: center;
  background: linear-gradient(160deg, var(--cream) 55%, var(--accent-light) 100%);
  padding: 5rem 2rem 4rem;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -80px; right: -80px;
  width: 420px; height: 420px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(193,125,90,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.hero::after {
  content: '';
  position: absolute;
  bottom: -60px; left: -40px;
  width: 300px; height: 300px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(74,139,140,0.07) 0%, transparent 70%);
  pointer-events: none;
}
.hero-inner {
  max-width: 1080px;
  margin: 0 auto;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 4rem;
  align-items: center;
}
.hero-eyebrow {
  font-family: var(--sans);
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 24px; height: 1px;
  background: var(--accent);
}
.hero h1 {
  font-family: var(--serif);
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  font-weight: 500;
  line-height: 1.15;
  color: var(--dark);
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}
.hero h1 em {
  font-style: italic;
  color: var(--accent);
}
.hero-bio {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 520px;
  line-height: 1.8;
  margin-bottom: 2rem;
}
.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 2.5rem;
}
.tag {
  font-size: 0.78rem;
  font-weight: 500;
  padding: 0.3rem 0.8rem;
  border-radius: 99px;
  background: var(--warm-white);
  border: 1px solid var(--sand);
  color: var(--brown);
  letter-spacing: 0.02em;
}
.tag.teal { background: var(--teal-light); border-color: #b0d5d5; color: var(--teal); }
.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--sans);
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.7rem 1.5rem;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover { background: var(--brown); color: #fff; transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-outline {
  background: transparent;
  color: var(--text);
  border: 1.5px solid var(--sand);
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-1px); }

.hero-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--sand);
}
.hero-card-label {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1rem;
}
.stat-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.25rem;
}
.stat { text-align: center; padding: 0.75rem; background: var(--warm-white); border-radius: var(--radius-sm); }
.stat-number {
  font-family: var(--serif);
  font-size: 1.6rem;
  font-weight: 600;
  color: var(--accent);
  line-height: 1;
}
.stat-label { font-size: 0.72rem; color: var(--text-muted); margin-top: 0.25rem; }
.affiliation {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.6rem 0;
  border-top: 1px solid var(--sand);
  font-size: 0.82rem;
  color: var(--text-muted);
}
.affil-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
}

/* ── Sections ── */
section { padding: 5rem 2rem; }
section:nth-child(even) { background: var(--warm-white); }
.section-inner { max-width: 1080px; margin: 0 auto; }
.section-label {
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}
.section-title {
  font-family: var(--serif);
  font-size: clamp(1.75rem, 3vw, 2.4rem);
  font-weight: 500;
  color: var(--dark);
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}
.section-intro {
  font-size: 1rem;
  color: var(--text-muted);
  max-width: 600px;
  line-height: 1.8;
  margin-bottom: 3rem;
}

/* ── About ── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
}
.about-text p { color: var(--text); line-height: 1.85; margin-bottom: 1.25rem; }
.about-text p:last-child { margin-bottom: 0; }
.timeline { list-style: none; }
.timeline-item {
  display: flex;
  gap: 1rem;
  padding-bottom: 1.5rem;
  position: relative;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: 7px; top: 24px;
  width: 1px; height: calc(100% - 8px);
  background: var(--sand);
}
.timeline-item:last-child::before { display: none; }
.timeline-dot {
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--accent-light);
  border: 2px solid var(--accent);
  flex-shrink: 0;
  margin-top: 4px;
}
.timeline-year { font-size: 0.78rem; color: var(--text-muted); font-weight: 500; margin-bottom: 0.2rem; }
.timeline-title { font-size: 0.9rem; font-weight: 500; color: var(--dark); margin-bottom: 0.15rem; }
.timeline-sub { font-size: 0.82rem; color: var(--text-muted); }

/* ── Research ── */
.research-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}
.research-card {
  background: #fff;
  border: 1px solid var(--sand);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.research-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}
.research-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.research-card:hover::before { transform: scaleX(1); }
.research-card.teal::before { background: var(--teal); }
.research-icon { font-size: 1.5rem; margin-bottom: 1rem; }
.research-card h3 {
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--dark);
  margin-bottom: 0.5rem;
}
.research-card p { font-size: 0.875rem; color: var(--text-muted); line-height: 1.75; }

/* ── Publications ── */
.pub-filters {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
}
.filter-btn {
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.4rem 1rem;
  border-radius: 99px;
  border: 1.5px solid var(--sand);
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
}
.filter-btn.active, .filter-btn:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.pub-list { display: flex; flex-direction: column; gap: 1rem; }
.pub-item {
  background: #fff;
  border: 1px solid var(--sand);
  border-radius: var(--radius);
  padding: 1.5rem 1.75rem;
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  transition: all var(--transition);
}
.pub-item:hover { border-color: var(--bark); box-shadow: var(--shadow); }
.pub-year {
  font-family: var(--serif);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--accent);
  min-width: 44px;
  padding-top: 0.1rem;
}
.pub-content { flex: 1; }
.pub-title {
  font-family: var(--serif);
  font-size: 0.975rem;
  font-weight: 500;
  color: var(--dark);
  margin-bottom: 0.3rem;
  line-height: 1.5;
}
.pub-venue { font-size: 0.82rem; color: var(--text-muted); margin-bottom: 0.5rem; }
.pub-tags { display: flex; flex-wrap: wrap; gap: 0.35rem; }
.pub-tag {
  font-size: 0.7rem;
  padding: 0.15rem 0.6rem;
  border-radius: 99px;
  background: var(--warm-white);
  color: var(--brown);
  border: 1px solid var(--sand);
}
.pub-doi {
  font-size: 0.75rem;
  color: var(--accent);
  margin-top: 0.4rem;
  display: inline-block;
}
.pub-badge {
  font-size: 0.65rem;
  font-weight: 500;
  padding: 0.2rem 0.6rem;
  border-radius: 99px;
  background: var(--accent-light);
  color: var(--accent);
  border: 1px solid rgba(193,125,90,0.2);
  white-space: nowrap;
  margin-top: 0.25rem;
}

/* ── Talks ── */
.talks-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}
.talk-card {
  background: #fff;
  border: 1px solid var(--sand);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: all var(--transition);
}
.talk-card:hover { box-shadow: var(--shadow-md); transform: translateY(-1px); }
.talk-year { font-size: 0.78rem; font-weight: 500; color: var(--accent); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 0.5rem; }
.talk-title { font-family: var(--serif); font-size: 0.95rem; color: var(--dark); margin-bottom: 0.4rem; line-height: 1.5; }
.talk-venue { font-size: 0.82rem; color: var(--text-muted); }

/* ── Contact ── */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: start; }
.contact-text p { color: var(--text); line-height: 1.85; margin-bottom: 1rem; font-size: 1rem; }
.contact-links { display: flex; flex-direction: column; gap: 0.75rem; }
.contact-link {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: #fff;
  border: 1px solid var(--sand);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 0.875rem;
  transition: all var(--transition);
}
.contact-link:hover { border-color: var(--accent); color: var(--accent); transform: translateX(4px); }
.contact-link-icon { width: 36px; height: 36px; border-radius: 8px; background: var(--accent-light); display: flex; align-items: center; justify-content: center; font-size: 1rem; flex-shrink: 0; }

/* ── Footer ── */
.footer {
  background: var(--dark);
  color: rgba(255,255,255,0.5);
  padding: 2rem;
  text-align: center;
}
.footer-inner { max-width: 1080px; margin: 0 auto; }
.footer p { font-size: 0.82rem; margin-bottom: 0.4rem; }
.footer-links a { color: rgba(255,255,255,0.6); margin: 0 0.3rem; }
.footer-links a:hover { color: var(--accent); }

/* ── Animations ── */
.fade-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* ── Responsive ── */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px; left: 0; right: 0;
    background: var(--cream);
    border-bottom: 1px solid var(--sand);
    padding: 1rem 2rem 1.5rem;
    gap: 1rem;
  }
  .hero-inner { grid-template-columns: 1fr; }
  .hero-card { display: none; }
  .about-grid, .contact-grid { grid-template-columns: 1fr; gap: 2.5rem; }
}