/* ===== VARIABLES ===== */
:root {
  --color-primary: #0A2540;
  --color-primary-light: #123a5e;
  --color-accent: #00A8A8;
  --color-accent-light: #4fd1d1;
  --color-bg: #FFFFFF;
  --color-bg-alt: #F5F7FA;
  --color-text: #1A1A1A;
  --color-text-light: #5A6472;
  --font-heading: 'Poppins', sans-serif;
  --font-body: 'Inter', sans-serif;
  --radius: 10px;
  --shadow: 0 4px 16px rgba(10, 37, 64, 0.08);
  --transition: 0.25s ease;
  --max-width: 1100px;
}

/* ===== RESET ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
}
a { text-decoration: none; color: var(--color-accent); transition: var(--transition); }
a:hover { color: var(--color-primary); }
ul { list-style: none; }
img { max-width: 100%; display: block; }
h1, h2, h3, h4 { font-family: var(--font-heading); color: var(--color-primary); line-height: 1.3; }

/* ===== HEADER / NAV ===== */
.site-header {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  box-shadow: 0 1px 6px rgba(0,0,0,0.06);
  z-index: 100;
}
.navbar {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
}
.logo {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.3rem;
  color: var(--color-primary);
}
.logo span { color: var(--color-accent); font-weight: 500; }
.nav-links {
  display: flex;
  gap: 1.8rem;
}
.nav-links a {
  color: var(--color-text);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
}
.nav-links a.active { color: var(--color-accent); }
.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: -6px; left: 0;
  width: 100%; height: 2px;
  background: var(--color-accent);
}
.nav-lock { opacity: 0.75; font-size: 0.9rem; }
.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-primary);
}

/* ===== HERO (home) ===== */
.hero {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 60%, var(--color-accent) 150%);
  color: white;
  padding: 6rem 1.5rem 5rem;
  text-align: center;
}
.hero-content { max-width: 700px; margin: 0 auto; }
.hero h1 { color: white; font-size: 2.6rem; margin-bottom: 1.2rem; }
.hero p { font-size: 1.15rem; color: rgba(255,255,255,0.9); margin-bottom: 2rem; }
.hero-buttons { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

/* ===== PAGE HERO (other pages) ===== */
.page-hero {
  background: var(--color-bg-alt);
  padding: 4rem 1.5rem 3rem;
  text-align: center;
}
.page-hero h1 { font-size: 2.2rem; margin-bottom: 0.8rem; }
.page-hero p { color: var(--color-text-light); max-width: 650px; margin: 0 auto; }

/* ===== BUTTONS ===== */
.btn {
  display: inline-block;
  padding: 0.75rem 1.6rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  transition: var(--transition);
  border: 2px solid transparent;
  cursor: pointer;
}
.btn-primary {
  background: var(--color-accent);
  color: white;
}
.btn-primary:hover { background: var(--color-accent-light); color: white; transform: translateY(-2px); }
.btn-outline {
  border-color: white;
  color: white;
}
.btn-outline:hover { background: white; color: var(--color-primary); }
.page-hero .btn-outline, .section .btn-outline {
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.section .btn-outline:hover { background: var(--color-primary); color: white; }

/* ===== STATS BAR ===== */
.stats {
  display: flex;
  justify-content: center;
  gap: 3rem;
  flex-wrap: wrap;
  padding: 3rem 1.5rem;
  background: var(--color-bg-alt);
}
.stat { text-align: center; }
.stat-number {
  display: block;
  font-family: var(--font-heading);
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--color-accent);
}
.stat-label { color: var(--color-text-light); font-size: 0.9rem; }

/* ===== SECTIONS ===== */
.section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 4rem 1.5rem;
}
.section-alt { background: var(--color-bg-alt); max-width: 100%; }
.section-alt > * { max-width: var(--max-width); margin-left: auto; margin-right: auto; }
.section-title {
  text-align: center;
  font-size: 2rem;
  margin-bottom: 2.5rem;
}
.section-subtitle {
  text-align: center;
  color: var(--color-text-light);
  margin-bottom: 2rem;
}
.center-link { text-align: center; margin-top: 2rem; }

/* ===== CARDS ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2rem;
}
.card {
  background: white;
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow);
  transition: var(--transition);
}
.card:hover { transform: translateY(-6px); }
.card-icon { font-size: 2rem; margin-bottom: 1rem; }
.card h3 { margin-bottom: 0.8rem; font-size: 1.15rem; }
.card p { color: var(--color-text-light); margin-bottom: 1rem; font-size: 0.95rem; }
.card-link { font-weight: 600; font-size: 0.9rem; }

/* ===== NEWS PREVIEW (home) ===== */
.news-preview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}
.news-card {
  background: white;
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}
.news-date {
  display: inline-block;
  background: var(--color-accent);
  color: white;
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
  margin-bottom: 0.8rem;
}
.news-card h4 { font-size: 1rem; margin-bottom: 0.5rem; }
.news-card p { font-size: 0.9rem; color: var(--color-text-light); }

/* ===== JOIN SECTION ===== */
.join-section { text-align: center; }
.join-grid { max-width: 700px; margin: 0 auto; text-align: left; }
.join-list { margin: 1.5rem 0; }
.join-list li { margin-bottom: 0.8rem; }
.join-list { list-style: disc; padding-left: 1.2rem; }

/* ===== RESEARCH PAGE ===== */
.research-area {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
  padding: 3rem 1.5rem;
}
.research-area.reverse { direction: rtl; }
.research-area.reverse > * { direction: ltr; }
.research-text h2 { margin-bottom: 1rem; }
.research-text p { color: var(--color-text-light); margin-bottom: 1.2rem; }
.pub-tags { display: flex; gap: 0.6rem; flex-wrap: wrap; }
.pub-tags li {
  background: var(--color-bg-alt);
  color: var(--color-primary);
  font-size: 0.85rem;
  padding: 0.4rem 0.9rem;
  border-radius: 20px;
  font-weight: 500;
}
.placeholder-image {
  background: var(--color-bg-alt);
  border: 2px dashed #ccd6e0;
  border-radius: var(--radius);
  min-height: 220px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-light);
  font-size: 0.9rem;
}

/* ===== PUBLICATIONS PAGE (updated with links) ===== */

.filter-controls {
  background: var(--color-bg-alt);
  padding: 1.5rem;
  border-radius: var(--radius);
  margin-bottom: 2rem;
}

.filter-group {
  margin-bottom: 1.5rem;
}

.filter-group:last-child {
  margin-bottom: 0;
}

.filter-group label {
  display: block;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 0.8rem;
  font-size: 0.95rem;
}

.filter-bar {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
}

.filter-btn {
  background: white;
  border: 1px solid #ddd;
  padding: 0.5rem 1.2rem;
  border-radius: 20px;
  cursor: pointer;
  font-weight: 500;
  color: var(--color-text);
  transition: var(--transition);
  font-size: 0.9rem;
}

.filter-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.filter-btn.active {
  background: var(--color-accent);
  color: white;
  border-color: var(--color-accent);
}

.pub-list {
  padding-left: 1.5rem;
}

.pub-item {
  padding: 1.5rem 0;
  border-bottom: 1px solid #eef1f4;
  position: relative;
}

.pub-item:last-child {
  border-bottom: none;
}

.pub-type-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.25rem 0.8rem;
  border-radius: 12px;
  margin-bottom: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.journal-badge {
  background: #e8f5f5;
  color: var(--color-accent);
}

.patent-badge {
  background: #fef3e8;
  color: #d97706;
}

.pub-citation {
  font-size: 0.95rem;
  line-height: 1.7;
}

.pub-citation strong {
  font-weight: 700;
}

.pub-citation em {
  font-style: italic;
}

/* Article title links */
.pub-link {
  color: var(--color-primary);
  font-weight: 600;
  border-bottom: 2px solid var(--color-accent);
  transition: var(--transition);
}

.pub-link:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-primary);
}

/* Highlight/press links */
.pub-links {
  display: inline-block;
  margin-left: 0.5rem;
  white-space: nowrap;
}

.highlight-link {
  display: inline-block;
  color: white;
  background: var(--color-accent);
  font-size: 0.7rem;
  font-weight: 600;
  padding: 0.25rem 0.7rem;
  border-radius: 10px;
  margin-left: 0.5rem;
  transition: var(--transition);
  vertical-align: middle;
}

.highlight-link:hover {
  background: var(--color-primary);
  color: white;
}

.pub-citation .badge {
  display: inline-block;
  background: var(--color-accent);
  color: white;
  font-size: 0.7rem;
  padding: 0.25rem 0.7rem;
  border-radius: 10px;
  margin-left: 0.5rem;
  vertical-align: middle;
  font-style: normal;
  font-weight: 600;
}

.pub-stats {
  text-align: center;
  padding: 2rem 1.5rem;
}

.pub-stats h3 {
  margin-bottom: 1.5rem;
}

/* Responsive for long citations on mobile */
@media (max-width: 600px) {
  .pub-citation {
    font-size: 0.9rem;
    line-height: 1.6;
  }
  
  .pub-links {
    display: block;
    margin-left: 0;
    margin-top: 0.6rem;
    white-space: normal;
  }
  
  .highlight-link {
    margin-left: 0;
    margin-right: 0.4rem;
    margin-bottom: 0.3rem;
  }
}

/* ===== TEAM PAGE ===== */
.pi-card {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 2.5rem;
  align-items: center;
}
.pi-placeholder { min-height: 220px; border-radius: var(--radius); }
.pi-title { color: var(--color-accent); font-weight: 600; margin-bottom: 1rem; }
.pi-bio p { color: var(--color-text-light); margin-bottom: 1.2rem; }
.pi-links a { margin-right: 1.2rem; font-weight: 600; font-size: 0.9rem; }

/* Make real <img> team photos behave like the placeholders did */
.team-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;      /* circular */
  object-fit: cover;        /* crops nicely, no squishing */
  margin: 0 auto 1rem;
  display: block;
  box-shadow: var(--shadow);
}

.pi-photo {
  width: 220px;
  height: 220px;
  border-radius: var(--radius);  /* rounded square for PI */
  object-fit: cover;
  display: block;
}

.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
}
.team-card { background: white; border-radius: var(--radius); padding: 1.5rem; text-align: center; box-shadow: var(--shadow); }
.team-placeholder { min-height: 160px; border-radius: 50%; margin: 0 auto 1rem; width: 160px; }
.team-role { color: var(--color-accent); font-weight: 600; font-size: 0.85rem; }
.team-area { color: var(--color-text-light); font-size: 0.85rem; }

.alumni-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
}
.alumni-column h4 { margin-bottom: 1rem; }
.alumni-column li { padding: 0.4rem 0; color: var(--color-text-light); font-size: 0.95rem; }

/* ===== NEWS TIMELINE ===== */
.timeline { position: relative; padding-left: 2rem; border-left: 3px solid var(--color-bg-alt); }
.timeline-item { margin-bottom: 2.5rem; position: relative; }
.timeline-item::before {
  content: '';
  position: absolute;
  left: -2.45rem;
  top: 0.3rem;
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 3px solid white;
}
.timeline-date {
  display: block;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 0.4rem;
  font-size: 0.9rem;
}
.timeline-content h3 { font-size: 1.1rem; margin: 0.4rem 0; }
.timeline-content p { color: var(--color-text-light); font-size: 0.95rem; }
.badge-talk { background: #4a6fa5; }
.badge-award { background: #c48f00; }
.badge-pub { background: var(--color-accent); }

/* ===== RESOURCES / PASSWORD GATE ===== */
.password-gate {
  max-width: 420px;
  margin: 0 auto;
  text-align: center;
  background: var(--color-bg-alt);
  padding: 2.5rem;
  border-radius: var(--radius);
}
.password-gate input {
  width: 100%;
  padding: 0.7rem 1rem;
  margin: 1.2rem 0;
  border: 1px solid #ccd6e0;
  border-radius: var(--radius);
  font-size: 1rem;
}
.password-error { color: #c0392b; font-size: 0.85rem; min-height: 1.2rem; }
.hidden { display: none; }
.resource-list li { padding: 0.6rem 0; font-size: 1rem; }
.resource-note { color: var(--color-text-light); font-size: 0.85rem; margin-top: 1.5rem; }

/* ===== FOOTER ===== */
.site-footer {
  background: var(--color-primary);
  color: rgba(255,255,255,0.85);
  text-align: center;
  padding: 2rem 1.5rem;
  font-size: 0.9rem;
}
.footer-links a { color: var(--color-accent-light); margin: 0 0.3rem; }

/* ===== RESPONSIVE ===== */
@media (max-width: 850px) {
  .research-area, .research-area.reverse { grid-template-columns: 1fr; direction: ltr; }
  .pi-card { grid-template-columns: 1fr; text-align: center; }
  .alumni-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%; left: 0; right: 0;
    background: white;
    flex-direction: column;
    padding: 1rem 1.5rem;
    box-shadow: 0 4px 10px rgba(0,0,0,0.08);
  }
  .nav-links.open { display: flex; }
  .hero h1 { font-size: 2rem; }
}