/* ── Reset & Base ── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 17.5px; }
body {
  font-family: 'Inter', sans-serif;
  color: #2c2c2c;
  background: #fafafa;
  line-height: 1.7;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ── Navigation ── */
nav {
  position: fixed; top: 0; left: 0; right: 0;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  z-index: 100;
  padding: 0 2rem;
}
nav .nav-inner {
  max-width: 1400px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  height: 60px;
}
nav .logo {
  font-family: 'Playfair Display', serif;
  font-weight: 700; font-size: 1.25rem;
  color: #1a1a1a;
}
nav .nav-links { display: flex; gap: 2rem; list-style: none; }
nav .nav-links a {
  font-size: 0.9rem; font-weight: 500; color: #555;
  transition: color 0.2s; position: relative;
}
nav .nav-links a:hover { color: #1a1a1a; }
nav .nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 0; width: 0;
  height: 2px; background: #7c3aed; transition: width 0.3s;
}
nav .nav-links a:hover::after { width: 100%; }
nav .nav-links a.active { color: #7c3aed; }
nav .nav-links a.active::after { width: 100%; }
.menu-toggle { display: none; background: none; border: none; cursor: pointer; padding: 4px; }
.menu-toggle span { display: block; width: 22px; height: 2px; background: #333; margin: 5px 0; transition: 0.3s; }

/* ── Hero / Intro ── */
.hero {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 100px 2rem 60px;
  background: linear-gradient(135deg, #fafafa 0%, #f0f0ff 100%);
}
.hero-inner {
  max-width: 1400px; width: 100%;
  display: flex; align-items: center; gap: 4rem;
}
.hero-photo { flex: 0 0 300px; }
.hero-photo img {
  width: 300px; height: 300px;
  object-fit: cover; object-position: center top;
  border-radius: 50%;
  box-shadow: 0 16px 48px rgba(124,58,237,0.12), 0 4px 16px rgba(0,0,0,0.08);
  border: 4px solid #fff;
}
.hero-text { flex: 1; }
.hero-text h1 {
  font-family: 'Playfair Display', serif;
  font-size: 2.8rem; font-weight: 700;
  line-height: 1.2; margin-bottom: 0.5rem;
  color: #1a1a1a;
}
.hero-text .tagline {
  font-size: 1.1rem; color: #7c3aed;
  margin-bottom: 0.5rem; font-weight: 600;
}
.hero-text .affiliation {
  font-size: 0.95rem; color: #888; margin-bottom: 1.2rem;
}
.hero-text p { font-size: 0.95rem; color: #555; max-width: 780px; line-height: 1.8; text-align: justify; }
.social-links { margin-top: 1.5rem; display: flex; gap: 0.8rem; flex-wrap: wrap; }
.social-links a {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.5rem 1rem;
  border: 1px solid #ddd; border-radius: 8px;
  font-size: 0.85rem; font-weight: 500; color: #555;
  transition: all 0.2s;
}
.social-links a:hover {
  border-color: #7c3aed; color: #7c3aed;
  box-shadow: 0 2px 12px rgba(124,58,237,0.1);
}
.edu-badges {
  display: flex; flex-direction: column; align-items: flex-start; gap: 0.5rem; margin-top: 1.2rem;
}
.edu-badge {
  display: inline-flex; align-items: center; gap: 0.4rem;
  background: #fff; border: 1px solid #e8e8e8;
  border-radius: 20px; padding: 0.35rem 0.85rem;
  font-size: 0.8rem; color: #666;
}
.edu-badge .dot {
  width: 6px; height: 6px; border-radius: 50%;
}

/* ── Page Content (non-hero subpages) ── */
.page-content {
  padding-top: 100px; padding-bottom: 60px; min-height: 100vh;
}
.page-content section { padding: 0 2rem 80px; }
.page-content section:first-child { padding-top: 0; }

/* ── Section Shared ── */
section { padding: 80px 2rem; }
.section-inner { max-width: 1400px; margin: 0 auto; }
.section-header { margin-bottom: 2.5rem; }
.section-title {
  font-family: 'Playfair Display', serif;
  font-size: 2rem; font-weight: 700;
  margin-bottom: 0.3rem; color: #1a1a1a;
}
.section-subtitle { color: #888; font-size: 0.95rem; }

/* ── Research ── */
.research-grid {
  display: grid; grid-template-columns: 1fr;
  gap: 1.5rem;
}
.research-card {
  background: #fafafa; border: 1px solid #eee;
  border-radius: 14px; padding: 2rem;
  transition: transform 0.25s, box-shadow 0.25s;
  position: relative; overflow: hidden;
}
.research-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 3px; border-radius: 14px 14px 0 0;
}
.research-card:nth-child(1)::before { background: linear-gradient(90deg, #7c3aed, #a78bfa); }
.research-card:nth-child(2)::before { background: linear-gradient(90deg, #0891b2, #67e8f9); }
.research-card:nth-child(3)::before { background: linear-gradient(90deg, #059669, #6ee7b7); }
.research-card:nth-child(4)::before { background: linear-gradient(90deg, #d97706, #fcd34d); }
.research-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0,0,0,0.08);
}
.research-card .icon {
  width: 48px; height: 48px;
  border-radius: 12px; display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; margin-bottom: 1rem;
}
.research-card h3 {
  font-size: 1.05rem; font-weight: 600; margin-bottom: 0.6rem;
  color: #1a1a1a;
}
.research-card p { font-size: 0.88rem; color: #666; line-height: 1.7; }
.research-card .research-tags {
  margin-top: 1rem; display: flex; flex-direction: column; align-items: flex-start; gap: 0.4rem;
}
.research-card .research-tags span,
.research-card .research-tags a {
  font-size: 0.72rem; font-weight: 500; padding: 0.2rem 0.6rem;
  background: #f0f0f0; border-radius: 4px; color: #777;
  transition: background 0.2s, color 0.2s;
  text-decoration: none; display: inline-block;
}
.research-card .research-tags a:hover {
  background: #7c3aed; color: #fff;
}

/* ── Publications ── */
.pub-section-label {
  font-size: 0.8rem; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.08em; color: #999; margin: 2rem 0 1rem;
  padding-bottom: 0.5rem; border-bottom: 1px solid #eee;
}
.pub-list { display: flex; flex-direction: column; gap: 0.4rem; }
.pub-item {
  background: #fafafa; border: 1px solid #eee;
  border-radius: 12px; padding: 1rem 1.2rem;
  transition: box-shadow 0.2s;
  border-left: 3px solid transparent;
}
.pub-item[data-type="under-review"] { border-left-color: #f59e0b; }
.pub-item[data-type="published"] { border-left-color: #10b981; }
.pub-item:hover { box-shadow: 0 4px 16px rgba(0,0,0,0.05); }
.pub-item .pub-venue {
  display: inline-block;
  font-size: 0.72rem; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.2rem 0.55rem; border-radius: 4px;
  margin-bottom: 0.5rem;
}
.pub-item h3 {
  font-size: 0.98rem; font-weight: 600; margin-bottom: 0.35rem;
  color: #1a1a1a; line-height: 1.5;
}
.pub-item .authors { font-size: 0.85rem; color: #777; line-height: 1.6; }
.pub-item .authors strong { color: #7c3aed; font-weight: 600; }
.pub-item .pub-journal {
  font-size: 0.82rem; color: #999; font-style: italic; margin-top: 0.3rem;
}
.pub-item .pub-links, .pub-links { margin-top: 0.6rem; display: flex; gap: 0.5rem; flex-wrap: wrap; }
.pub-item .pub-links a, .pub-links a {
  font-size: 0.75rem; font-weight: 500; padding: 0.2rem 0.55rem;
  border: 1px solid #ddd; border-radius: 4px; color: #666;
  transition: all 0.2s;
}
.pub-item .pub-links a:hover, .pub-links a:hover { border-color: #7c3aed; color: #7c3aed; }
.venue-review { background: #fef3e2; color: #b45309; }
.venue-journal { background: #e6f7ed; color: #1a7f42; }

/* ── Awards ── */
.awards-list { display: flex; flex-direction: column; gap: 1rem; }
.award-item {
  display: flex; align-items: flex-start; gap: 1rem;
  padding: 1.2rem 1.5rem;
  background: #fafafa; border: 1px solid #eee;
  border-radius: 10px;
}
.award-year {
  flex: 0 0 auto;
  font-size: 0.8rem; font-weight: 600; color: #7c3aed;
  background: #f3eeff; padding: 0.3rem 0.6rem; border-radius: 6px;
  white-space: nowrap;
}
.award-text h4 { font-size: 0.92rem; font-weight: 600; color: #1a1a1a; }
.award-text p { font-size: 0.82rem; color: #888; }

/* ── Photography ── */
.photo-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.2rem;
}
@media (max-width: 640px) {
  .photo-grid { grid-template-columns: 1fr; }
}
.photo-card {
  position: relative; border-radius: 12px; overflow: hidden;
  aspect-ratio: 4/3;
  background: #e5e5e5;
  cursor: pointer;
}
.photo-card img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.4s ease;
}
.photo-card:hover img { transform: scale(1.05); }
.photo-card .photo-caption {
  position: absolute; bottom: 0; left: 0; right: 0;
  background: linear-gradient(transparent, rgba(0,0,0,0.7));
  color: #fff; padding: 2rem 1rem 1rem;
  font-size: 0.85rem; font-weight: 500;
  opacity: 0; transition: opacity 0.3s;
  pointer-events: none;
}
.photo-card:hover .photo-caption { opacity: 1; }

/* ── Lightbox ── */
.lightbox-overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.92);
  z-index: 1000;
  display: flex; align-items: center; justify-content: center;
  opacity: 0; visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
  cursor: zoom-out;
}
.lightbox-overlay.active { opacity: 1; visibility: visible; }
.lightbox-overlay img {
  max-width: 90vw; max-height: 85vh;
  object-fit: contain;
  border-radius: 6px;
  box-shadow: 0 8px 40px rgba(0,0,0,0.5);
  cursor: default;
  transform: scale(0.92);
  transition: transform 0.3s ease;
}
.lightbox-overlay.active img { transform: scale(1); }
.lightbox-caption {
  position: absolute; bottom: 2rem; left: 50%;
  transform: translateX(-50%);
  color: rgba(255,255,255,0.85);
  font-size: 0.9rem; font-weight: 500;
  text-align: center;
  pointer-events: none;
}
.lightbox-close {
  position: absolute; top: 1.5rem; right: 2rem;
  background: none; border: none;
  color: rgba(255,255,255,0.7); font-size: 2rem;
  cursor: pointer; line-height: 1;
  transition: color 0.2s;
}
.lightbox-close:hover { color: #fff; }
.lightbox-nav {
  position: absolute; top: 50%; transform: translateY(-50%);
  background: rgba(255,255,255,0.1); border: none;
  color: rgba(255,255,255,0.8); font-size: 2rem;
  width: 48px; height: 48px; border-radius: 50%;
  cursor: pointer; display: flex; align-items: center; justify-content: center;
  transition: background 0.2s, color 0.2s;
}
.lightbox-nav:hover { background: rgba(255,255,255,0.2); color: #fff; }
.lightbox-prev { left: 1.5rem; }
.lightbox-next { right: 1.5rem; }

/* ── Footer ── */
footer {
  text-align: center; padding: 2.5rem 2rem;
  font-size: 0.85rem; color: #999;
  border-top: 1px solid #eee;
  background: #fafafa;
}
footer a { color: #7c3aed; }

/* ── Responsive ── */
@media (max-width: 768px) {
  .hero-inner { flex-direction: column; text-align: center; gap: 2rem; }
  .hero-photo { flex: none; }
  .hero-photo img { width: 200px; height: 200px; }
  .hero-text h1 { font-size: 2rem; }
  .social-links { justify-content: center; }
  .edu-badges { justify-content: center; }
  .hero-text p { margin: 0 auto; }
  nav .nav-links { display: none; }
  nav .nav-links.open {
    display: flex; flex-direction: column;
    position: absolute; top: 60px; left: 0; right: 0;
    background: rgba(255,255,255,0.98); padding: 1rem 2rem;
    border-bottom: 1px solid #eee; gap: 1rem;
  }
  .menu-toggle { display: block; }
  .section-title { font-size: 1.6rem; }
  .research-grid { grid-template-columns: 1fr; } /* already 1fr, kept for clarity */
  .award-item { flex-direction: column; gap: 0.5rem; }
}

/* ── Scroll Animation ── */
.fade-in {
  opacity: 0; transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }