:root {
  --bg: #ffffff;
  --text: #2d3748;
  --text-light: #718096;
  --primary: #1a365d;
  --accent: #2b6cb0;
  --surface: #f7fafc;
  --border: #e2e8f0;
  --font-main: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
  font-family: var(--font-main);
  color: var(--text);
  line-height: 1.7;
  background: var(--bg);
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Header & Navigation */
header {
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(5px);
  z-index: 100;
}

.nav-container {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.5rem;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  letter-spacing: -0.5px;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

nav a {
  text-decoration: none;
  color: var(--text-light);
  font-weight: 500;
  font-size: 0.95rem;
}

nav a:hover {
  color: var(--primary);
}

/* Hero Section */
.hero {
  padding: 5rem 0 3.5rem;
  border-bottom: 1px solid var(--border);
}

.hero h1 {
  font-size: 2.5rem;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.subtitle {
  font-size: 1.25rem;
  color: var(--accent);
  margin-bottom: 0.25rem;
}

/* Multi-line Affiliation */
.affiliation {
  margin-top: 0.5rem;
  margin-bottom: 1.25rem;
}

.affiliation p {
  color: var(--text-light);
  line-height: 1.4;
  margin: 0;
}

/* Contact Details */
.contact-info {
  list-style: none;
  padding: 0;
  margin-bottom: 2.75rem; /* Expanded gap before buttons */
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.95rem;
}

.contact-info strong {
  color: var(--primary);
  min-width: 60px;
  display: inline-block;
}

.contact-info a {
  color: var(--accent);
  text-decoration: none;
}

.contact-info a:hover {
  text-decoration: underline;
}

/* Action Buttons */
.hero-actions {
  display: flex;
  gap: 1rem;
}

.btn {
  display: inline-block;
  padding: 0.6rem 1.2rem;
  border-radius: 6px;
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.btn.primary {
  background: var(--primary);
  color: #ffffff;
}

.btn.primary:hover {
  background: var(--accent);
}

.btn.secondary {
  border: 1px solid var(--border);
  color: var(--text);
  background: #ffffff;
}

.btn.secondary:hover {
  background: var(--surface);
}

/* General Sections */
.section {
  padding: 4rem 0;
}

.section h2 {
  font-size: 1.6rem;
  color: var(--primary);
  margin-bottom: 1.25rem;
}

.bg-light {
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

/* Research Cards */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card {
  background: #ffffff;
  padding: 1.5rem;
  border-radius: 8px;
  border: 1px solid var(--border);
}

.card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
  color: var(--primary);
}

/* Publication List */
.pub-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.pub-list li {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
}

.pub-list a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
}

.pub-list a:hover {
  text-decoration: underline;
}

.conf {
  color: var(--text-light);
  font-size: 0.9rem;
}

/* Footer */
footer {
  padding: 3rem 0;
  text-align: center;
  border-top: 1px solid var(--border);
  color: var(--text-light);
  font-size: 0.9rem;
}

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

footer a:hover {
  text-decoration: underline;
}

/* Publication Categories */
.pub-category {
  margin-top: 3rem;
}

.pub-category h3 {
  font-size: 1.3rem;
  color: var(--primary);
  margin-bottom: 1.25rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid var(--border);
}

/* Enable button wrapping for multiple profile links */
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* Generous space beneath all paragraphs in content sections */
.section p {
  margin-bottom: 1.0rem; /* Increase to 3rem if you want even more space */
  line-height: 1.85;
}

.section p:last-child {
  margin-bottom: 0;
}
/* Two-Column Hero Layout */
.hero-layout {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 3rem;
}

.hero-content {
  flex: 1;
}

/* Profile Photo Styling */
.hero-image {
  flex-shrink: 0;
}

.hero-image img {
  width: 260px;
  height: 330px;
  object-fit: cover;
  border-radius: 12px;
  border: 1px solid var(--border);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  display: block;
}

/* Responsive adjustment for mobile screens */
@media (max-width: 768px) {
  .hero-layout {
    flex-direction: column-reverse;
    align-items: flex-start;
    gap: 2rem;
  }

  .hero-image img {
    width: 200px;
    height: 250px;
  }
}

/* Supervised Group Styles */
.supervision-section {
  margin-top: 4rem;
}

.group-title {
  font-size: 1.25rem;
  color: var(--primary);
  margin: 2rem 0 1rem;
  padding-bottom: 0.35rem;
  border-bottom: 2px solid var(--border);
}

.people-list {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.people-list li {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
  line-height: 1.6;
}

.person-name {
  font-weight: 600;
  color: var(--text);
}

.person-role, .thesis {
  color: var(--text-light);
  font-size: 0.95rem;
}

.next-pos {
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 500;
}

/* Callout Box for Prospective Students */
.callout-box {
  margin-top: 3rem;
  padding: 1.5rem;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
}

.callout-box h4 {
  color: var(--primary);
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
}

.callout-box p {
  color: var(--text);
  margin-bottom: 0.5rem;
}