/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --text:       #1a1a1a;
  --text-light: #555;
  --accent:     #2563eb;
  --accent-hover: #1d4ed8;
  --border:     #e5e7eb;
  --bg:         #ffffff;
  --bg-subtle:  #f9fafb;
  --max-w:      1120px;
  --font: 'Georgia', 'Times New Roman', serif;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
}

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

/* ===== NAV ===== */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.25rem;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-name {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
}

.nav-links { display: flex; gap: 1.5rem; }
.nav-links a {
  font-size: 0.9rem;
  color: var(--text-light);
  text-decoration: none;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--accent); text-decoration: none; }

/* ===== MAIN LAYOUT ===== */
main {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.25rem 4rem;
}

section {
  padding-top: 3.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}
section:last-child { border-bottom: none; }

h2 {
  font-family: var(--font);
  font-size: 1.4rem;
  font-weight: normal;
  margin-bottom: 1.25rem;
  color: var(--text);
}

.section-note {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 1.25rem;
  margin-top: -0.75rem;
}

/* ===== ABOUT ===== */
#about { border-bottom: 1px solid var(--border); }

.about-grid {
  display: grid;
  grid-template-columns: 148px 1fr;
  gap: 1.75rem;
  align-items: start;
  padding-top: 2.5rem;
  padding-bottom: 2rem;
}

.about-photo img {
  width: 148px;
  height: 148px;
  border-radius: 50%;
  object-fit: cover;
  background: #e5e7eb;
  display: block;
}

.about-text h1 {
  font-family: var(--font);
  font-size: 1.75rem;
  font-weight: normal;
  margin-bottom: 0.2rem;
}

.affiliation {
  font-size: 0.95rem;
  color: var(--text-light);
  margin-bottom: 0.9rem;
}

.bio {
  font-size: 0.95rem;
  color: var(--text);
  margin-bottom: 0.6rem;
}

.links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  margin-top: 1rem;
}

.links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  border: 1px solid var(--border);
  padding: 0.2rem 0.65rem;
  border-radius: 4px;
  transition: background 0.15s, border-color 0.15s;
}
.links a:hover {
  background: #eff6ff;
  border-color: var(--accent);
  text-decoration: none;
}

/* ===== NEWS ===== */
.news-list {
  list-style: none;
  font-size: 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.news-list li {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
}

.date {
  flex-shrink: 0;
  font-size: 0.8rem;
  color: var(--text-light);
  white-space: nowrap;
}

/* ===== PUBLICATIONS ===== */
.pub-list { display: flex; flex-direction: column; gap: 1.75rem; }

.pub-item {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1.25rem;
  align-items: start;
}

.pub-thumb {
  width: 120px;
  height: 80px;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  flex-shrink: 0;
}

.pub-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.pub-title {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.2rem;
  line-height: 1.4;
}

.pub-title a { color: var(--text); }
.pub-title a:hover { color: var(--accent); }

.pub-authors {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 0.15rem;
}

.pub-venue {
  font-size: 0.875rem;
  color: var(--text-light);
  font-style: italic;
  margin-bottom: 0.5rem;
}

.pub-links { display: flex; flex-wrap: wrap; gap: 0.4rem; }

.tag {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--accent);
  border: 1px solid #bfdbfe;
  background: #eff6ff;
  padding: 0.1rem 0.55rem;
  border-radius: 3px;
  transition: background 0.15s;
}
.tag:hover { background: #dbeafe; text-decoration: none; }

/* ===== RESEARCH PROJECTS ===== */
.project-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.project-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.1rem 1.25rem;
  background: var(--bg-subtle);
  transition: border-color 0.15s, box-shadow 0.15s;
}

.project-card:hover {
  border-color: #93c5fd;
  box-shadow: 0 2px 8px rgba(37,99,235,0.07);
}

.project-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
  color: var(--text);
}

.project-card p {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 0.75rem;
  line-height: 1.55;
}

/* ===== EXPERIENCE ===== */
.exp-list { display: flex; flex-direction: column; gap: 1.75rem; }

.exp-item {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 1.25rem;
  align-items: start;
}

.exp-left img {
  width: 56px;
  height: 56px;
  border-radius: 8px;
  object-fit: contain;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  padding: 4px;
}

.exp-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 0.1rem;
}

.exp-org {
  font-size: 0.9rem;
  margin-bottom: 0.1rem;
}

.exp-date {
  font-size: 0.8rem;
  color: var(--text-light);
  margin-bottom: 0.4rem;
}

.exp-desc {
  font-size: 0.875rem;
  color: var(--text-light);
  line-height: 1.55;
}

/* ===== BLOG ===== */
.blog-list { list-style: none; display: flex; flex-direction: column; gap: 0; }

.blog-item a {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 0.65rem 0;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  transition: color 0.15s;
}
.blog-item:last-child a { border-bottom: none; }
.blog-item a:hover .blog-title { color: var(--accent); }

.blog-title { font-size: 0.95rem; }
.blog-meta { font-size: 0.8rem; color: var(--text-light); flex-shrink: 0; margin-left: 1rem; }

/* ===== FOOTER ===== */
footer {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 1.5rem 1.25rem 2.5rem;
  font-size: 0.8rem;
  color: var(--text-light);
  text-align: center;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 600px) {
  .nav-inner,
  main,
  footer {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  .about-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .about-photo img { margin: 0 auto; }
  .links { justify-content: center; }

  .pub-item {
    grid-template-columns: 1fr;
  }
  .pub-thumb { width: 100%; height: 120px; }

  .project-grid { grid-template-columns: 1fr; }

  .exp-item {
    grid-template-columns: 1fr;
  }
  .exp-left { display: none; }

  .news-list li {
    flex-wrap: wrap;
    gap: 0.1rem;
  }

  .blog-item a { flex-direction: column; gap: 0.2rem; }
  .blog-meta { margin-left: 0; }
}