@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=Playfair+Display:wght@400;600;700&display=swap');

:root {
  --primary-navy: #0f172a;
  --secondary-navy: #1e293b;
  --accent-green: #10b981;
  --accent-green-hover: #059669;
  --text-main: #334155;
  --text-light: #64748b;
  --bg-main: #ffffff;
  --bg-alt: #f8fafc;
  --border-color: #e2e8f0;
  
  --font-serif: 'Playfair Display', serif;
  --font-sans: 'Inter', sans-serif;
  
  --transition: all 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--text-main);
  background-color: var(--bg-main);
  line-height: 1.6;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  color: var(--primary-navy);
  font-weight: 700;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

ul {
  list-style: none;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 4px;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font-sans);
  border: none;
}

.btn-primary {
  background-color: var(--primary-navy);
  color: white;
}

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

.btn-outline {
  border: 1px solid var(--border-color);
  background-color: transparent;
  color: var(--primary-navy);
}

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

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-brand {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-navy);
}

.nav-links {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav-links a {
  font-size: 0.95rem;
  font-weight: 500;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--accent-green);
}

.hamburger {
  display: none;
  cursor: pointer;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--primary-navy);
}

/* Hero Section */
.hero {
  padding: 12rem 0 6rem;
  background-color: var(--bg-alt);
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-content h1 {
  font-size: 3.5rem;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

.hero-content p {
  font-size: 1.125rem;
  color: var(--text-light);
  margin-bottom: 2rem;
  max-width: 90%;
}

.hero-stats {
  display: flex;
  gap: 3rem;
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.stat-item h4 {
  font-size: 2rem;
  font-family: var(--font-sans);
  color: var(--primary-navy);
  margin-bottom: 0.25rem;
}

.stat-item p {
  font-size: 0.875rem;
  color: var(--text-light);
  margin: 0;
}

.hero-image img {
  width: 100%;
  border-radius: 8px;
  box-shadow: 0 20px 40px rgba(0,0,0,0.1);
  object-fit: cover;
  aspect-ratio: 4/5;
}

/* Sections General */
section {
  padding: 6rem 0;
}

.section-header {
  margin-bottom: 4rem;
  text-align: center;
}

.section-header h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.section-header p {
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
}

/* About Section */
.about {
  background-color: var(--bg-main);
}

.about .container {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 4rem;
}

.about-sidebar {
  position: sticky;
  top: 100px;
}

.about-sidebar img {
  width: 100%;
  border-radius: 8px;
  margin-bottom: 1.5rem;
}

.timeline {
  border-left: 2px solid var(--accent-green);
  padding-left: 1.5rem;
  margin-bottom: 2rem;
}

.timeline-item {
  position: relative;
  margin-bottom: 2rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -1.85rem;
  top: 0.25rem;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: var(--accent-green);
}

.timeline-date {
  font-size: 0.875rem;
  color: var(--accent-green);
  font-weight: 600;
  margin-bottom: 0.5rem;
  display: block;
}

.timeline-title {
  font-size: 1.25rem;
  margin-bottom: 0.25rem;
}

.timeline-subtitle {
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 0.5rem;
}

.philosophy-card {
  background-color: var(--bg-alt);
  padding: 2rem;
  border-radius: 8px;
  border-left: 4px solid var(--accent-green);
  margin: 2rem 0;
}

.philosophy-card h3 {
  margin-bottom: 1rem;
}

.philosophy-card p {
  font-style: italic;
  color: var(--text-main);
}

/* Research Grid */
.research {
  background-color: var(--bg-alt);
}

.research-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

.research-card {
  background-color: var(--bg-main);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2rem;
  transition: var(--transition);
}

.research-card:hover {
  box-shadow: 0 10px 30px rgba(0,0,0,0.05);
  border-color: var(--accent-green);
  transform: translateY(-5px);
}

.research-icon {
  color: var(--accent-green);
  font-size: 2rem;
  margin-bottom: 1.5rem;
}

.research-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.research-card p {
  color: var(--text-light);
  margin-bottom: 1.5rem;
}

.read-more {
  color: var(--accent-green);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.read-more:hover {
  gap: 0.75rem;
}

/* Publications */
.publications {
  background-color: var(--bg-main);
}

.pub-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.pub-item {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-color);
}

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

.pub-year {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-navy);
  font-family: var(--font-serif);
}

.pub-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background-color: rgba(16, 185, 129, 0.1);
  color: var(--accent-green);
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.pub-title {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

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

.pub-journal {
  font-style: italic;
  font-size: 0.875rem;
  margin-bottom: 1rem;
}

.pub-links {
  display: flex;
  gap: 1rem;
}

.pub-links a {
  font-size: 0.875rem;
  color: var(--accent-green);
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

/* Gallery */
.gallery {
  background-color: var(--bg-alt);
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.gallery-item {
  aspect-ratio: 1;
  overflow: hidden;
  border-radius: 8px;
  position: relative;
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.gallery-item:hover img {
  transform: scale(1.05);
}

.gallery-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 1.5rem;
  background: linear-gradient(transparent, rgba(0,0,0,0.8));
  color: white;
  opacity: 0;
  transition: var(--transition);
}

.gallery-item:hover .gallery-overlay {
  opacity: 1;
}

/* Contact Footer */
.footer {
  background-color: var(--primary-navy);
  color: white;
  padding: 5rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  margin-bottom: 4rem;
}

.footer-info h2 {
  color: white;
  margin-bottom: 1.5rem;
}

.footer-info p {
  color: #94a3b8;
  margin-bottom: 2rem;
  max-width: 400px;
}

.social-links {
  display: flex;
  gap: 1rem;
}

.social-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: rgba(255,255,255,0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  transition: var(--transition);
}

.social-icon:hover {
  background-color: var(--accent-green);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.form-group input, .form-group textarea {
  width: 100%;
  padding: 1rem;
  background-color: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 4px;
  color: white;
  font-family: var(--font-sans);
}

.form-group input:focus, .form-group textarea:focus {
  outline: none;
  border-color: var(--accent-green);
}

.footer-bottom {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid rgba(255,255,255,0.1);
  color: #94a3b8;
  font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 992px) {
  .hero .container, .about .container {
    grid-template-columns: 1fr;
  }
  
  .about-sidebar {
    position: static;
  }
  
  .research-grid {
    grid-template-columns: 1fr;
  }
  
  .gallery-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: white;
    flex-direction: column;
    padding: 2rem;
    gap: 1.5rem;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    clip-path: polygon(0 0, 100% 0, 100% 0, 0 0);
    transition: var(--transition);
  }
  
  .nav-links.active {
    clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
  }
  
  .hamburger {
    display: block;
  }
  
  .hero-content h1 {
    font-size: 2.5rem;
  }
  
  .hero-stats {
    flex-direction: column;
    gap: 1.5rem;
  }
  
  .pub-item {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }
  
  .gallery-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
  }
}