/* ── CSS VARIABLES ── */
:root {
  --navy: #0f2341;
  --blue: #1a4a8a;
  --sky: #2e7bbf;
  --accent: #c8922a;
  --light: #f4f7fb;
  --white: #ffffff;
  --text: #1e2a3a;
  --muted: #6b7a8d;
  --border: #dde3ed;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'DM Sans', sans-serif;
  background: var(--light);
  color: var(--text);
  line-height: 1.7;
}

/* ── NAVBAR ── */
nav {
  background: var(--white);
  border-bottom: 3px solid var(--sky);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 12px rgba(0,0,0,0.08);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.nav-logo {
  font-family: 'Crimson Pro', serif;
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--navy);
  padding: 14px 0;
  text-decoration: none;
  letter-spacing: 0.01em;
}
.nav-logo span { color: var(--sky); }
.nav-links {
  display: flex;
  gap: 4px;
  list-style: none;
}
.nav-links a {
  display: block;
  padding: 18px 14px;
  font-size: 0.83rem;
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  transition: color 0.2s;
  border-bottom: 3px solid transparent;
  margin-bottom: -3px;
}
.nav-links a:hover, .nav-links a.active {
  color: var(--sky);
  border-bottom-color: var(--sky);
}

/* ── HERO / PROFILE ── */
.hero {
  background: linear-gradient(135deg, var(--navy) 0%, #163563 50%, var(--blue) 100%);
  color: white;
  padding: 60px 24px 50px;
  overflow: hidden;
  position: relative;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 80% 20%, rgba(46,123,191,0.2) 0%, transparent 60%),
    radial-gradient(circle at 10% 80%, rgba(200,146,42,0.1) 0%, transparent 50%);
}
.hero-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: flex-end;
  gap: 48px;
  position: relative;
}
.hero-info {
  padding-bottom: 0;
  flex: 1;
}
.hero-name {
  font-family: 'Crimson Pro', serif;
  font-size: 2.8rem;
  font-weight: 300;
  line-height: 1.15;
  margin-bottom: 6px;
}
.hero-photo img { 
  width: 180px; 
  height: 180px; 
  object-fit: cover; 
  border-radius: 50%; 
}
.hero-name strong { font-weight: 600; }
.hero-title {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.7);
  margin-bottom: 16px;
}
.hero-quals {
  color: rgba(255,255,255,0.55);
  font-style: italic;
  margin-bottom: 20px;
  font-family: 'Crimson Pro', serif;
  font-size: 0.95rem;
}
.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}
.hero-tag {
  background: rgba(46,123,191,0.25);
  border: 1px solid rgba(46,123,191,0.4);
  border-radius: 20px;
  padding: 4px 14px;
  font-size: 0.78rem;
  color: rgba(255,255,255,0.85);
}
.hero-contacts {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.hero-contacts a {
  color: rgba(255,255,255,0.75);
  font-size: 0.82rem;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 6px;
}
.hero-contacts a:hover { color: #fff; }

/* ── TAB BAR ── */
.tabs-bar {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 57px;
  z-index: 90;
}
.tabs-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  gap: 0;
  overflow-x: auto;
}
.tab-btn {
  flex-shrink: 0;
  padding: 16px 22px;
  font-size: 0.83rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  border: none;
  background: none;
  cursor: pointer;
  border-bottom: 3px solid transparent;
  margin-bottom: -1px;
  transition: color 0.2s, border-color 0.2s;
  font-family: 'DM Sans', sans-serif;
}
.tab-btn.active, .tab-btn:hover {
  color: var(--sky);
  border-bottom-color: var(--sky);
}

/* ── MAIN CONTENT ── */
main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* ── SECTION HEADING ── */
.section-heading {
  font-family: 'Crimson Pro', serif;
  font-size: 1.65rem;
  font-weight: 600;
  color: var(--navy);
  border-left: 4px solid var(--sky);
  padding-left: 16px;
  margin: 40px 0 20px;
}
.section-heading:first-child { margin-top: 0; }

.subsection-heading {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--sky);
  margin: 32px 0 14px;
}

/* ── CARDS ── */
.card {
  background: var(--white);
  border-radius: 8px;
  border: 1px solid var(--border);
  padding: 28px 32px;
  margin-bottom: 20px;
}

/* ── PUBLICATION ITEM ── */
.pub-item {
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
  line-height: 1.65;
}
.pub-item:last-child { border-bottom: none; }
.pub-item .pub-title {
  font-weight: 500;
  color: var(--navy);
}
.pub-item .pub-authors { color: var(--muted); font-size: 0.85rem; }
.pub-item .pub-venue {
  font-style: italic;
  color: var(--sky);
  font-size: 0.85rem;
}
.pub-item .pub-doi {
  font-size: 0.78rem;
  color: var(--accent);
}

/* ── GRID ── */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

/* ── EXPERIENCE ROW ── */
.exp-row {
  display: flex;
  gap: 20px;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}
.exp-row:last-child { border-bottom: none; }
.exp-date {
  flex-shrink: 0;
  width: 130px;
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--accent);
  padding-top: 2px;
}
.exp-body h4 {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 2px;
}
.exp-body p {
  font-size: 0.85rem;
  color: var(--muted);
}

/* ── LIST ── */
.styled-list {
  list-style: none;
  padding: 0;
}
.styled-list li {
  padding: 7px 0 7px 20px;
  position: relative;
  font-size: 0.88rem;
  border-bottom: 1px dashed var(--border);
}
.styled-list li:last-child { border-bottom: none; }
.styled-list li::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 16px;
  width: 6px;
  height: 6px;
  background: var(--sky);
  border-radius: 50%;
}

/* ── GRANT/AWARD CARD ── */
.award-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 0 8px 8px 0;
  padding: 16px 20px;
  margin-bottom: 12px;
  font-size: 0.88rem;
}
.award-card h4 {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 4px;
}
.award-card p { color: var(--muted); }

/* ── BADGE ── */
.badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-right: 6px;
}
.badge-blue { background: #dbeeff; color: var(--sky); }
.badge-gold { background: #fff2db; color: #9a6e1a; }

/* ── RESEARCH INTEREST CARDS ── */
.card.interest {
  border-top: 3px solid var(--sky);
}
.card.interest .icon {
  font-size: 1.6rem;
  margin-bottom: 10px;
}
.card.interest h3 {
  font-size: 1rem;
  color: var(--navy);
  margin-bottom: 6px;
}
.card.interest p {
  font-size: 0.85rem;
  color: var(--muted);
}

/* ── FOOTER ── */
footer {
  background: var(--navy);
  color: rgba(255,255,255,0.55);
  text-align: center;
  padding: 28px 24px;
  font-size: 0.8rem;
}
footer a { color: rgba(255,255,255,0.7); }

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .hero-inner { flex-direction: column; align-items: flex-start; }
  .hero-photo img { width: 80px; height: 80px; object-fit: cover; border-radius: 50%; }
  .hero-name { font-size: 2rem; }
  .nav-links { display: none; }
  .exp-date { width: 90px; font-size: 0.72rem; }
  .grid-2 { grid-template-columns: 1fr; }
}

/* ── TIMELINE ── */
.timeline-wrap { margin-bottom: 8px; }
.tl-row {
  display: grid;
  grid-template-columns: 1fr 72px 1fr;
  align-items: start;
  margin-bottom: 0;
}
.tl-side { padding: 8px 0; }
.tl-left { display: flex; justify-content: flex-end; padding-right: 14px; }
.tl-right { padding-left: 14px; }
.tl-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  padding-top: 8px;
}
.tl-center::before {
  content: '';
  position: absolute;
  top: 0; bottom: -8px;
  left: 50%;
  width: 2px;
  background: linear-gradient(to bottom, var(--sky), var(--border));
  transform: translateX(-50%);
  z-index: 0;
}
.tl-row:last-child .tl-center::before {
  background: linear-gradient(to bottom, var(--border), transparent);
}
.tl-dot {
  width: 11px; height: 11px;
  border-radius: 50%;
  background: var(--sky);
  border: 2.5px solid var(--light);
  z-index: 1;
  flex-shrink: 0;
}
.tl-dot-muted { background: var(--muted); }
.tl-date {
  font-size: 10px;
  font-weight: 700;
  color: var(--sky);
  text-align: center;
  line-height: 1.25;
  margin-top: 4px;
  z-index: 1;
  letter-spacing: 0.02em;
}
.tl-muted { color: var(--muted) !important; }
.tl-card {
  background: var(--white);
  border-radius: var(--border-radius, 8px);
  border: 1px solid var(--border);
  padding: 10px 13px;
  max-width: 220px;
}
.tl-card-muted { opacity: 0.6; }
.tl-tag {
  font-size: 9px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--sky);
  margin-bottom: 4px;
}
.tl-card h4 {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--navy);
  line-height: 1.35;
  margin-bottom: 3px;
}
.tl-card p {
  font-size: 0.78rem;
  color: var(--muted);
  line-height: 1.45;
}
@media (max-width: 600px) {
  .tl-row { grid-template-columns: 1fr 56px 1fr; }
  .tl-left { padding-right: 8px; }
  .tl-right { padding-left: 8px; }
  .tl-card { max-width: 140px; }
  .tl-card h4 { font-size: 0.72rem; }
  .tl-card p { font-size: 0.68rem; }
}