/* Hero Section */
.hero-section {
  height: 100vh;
  min-height: 600px;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
  background-image: url('/images/hero-background.jpg'); /* Placeholder - add your image */
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-content {
  text-align: center;
  color: white;
  z-index: 2;
  padding: 2rem;
}

.hero-title {
  font-size: 4rem;
  font-weight: 300;
  margin-bottom: 1rem;
  letter-spacing: 2px;
}

.hero-subtitle {
  font-size: 1.5rem;
  font-weight: 300;
  margin-bottom: 0.5rem;
  opacity: 0.9;
}

.hero-affiliation {
  font-size: 1.2rem;
  opacity: 0.8;
}

/* Content Sections */
.content-section {
  padding: 80px 0;
  min-height: 50vh;
}

.content-section.alt-bg {
  background-color: #f8f9fa;
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 2rem;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 300;
  margin-bottom: 2rem;
  color: #1a1a2e;
  border-bottom: 3px solid #0f3460;
  padding-bottom: 1rem;
}

.section-content {
  font-size: 1.1rem;
  line-height: 1.8;
  color: #333;
}

/* Education Items */
.education-item {
  margin-bottom: 2.5rem;
  padding: 1.5rem;
  background: white;
  border-left: 4px solid #0f3460;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.education-item h3 {
  margin-top: 0;
  color: #1a1a2e;
  font-size: 1.5rem;
}

.institution {
  font-weight: 600;
  color: #0f3460;
  margin-bottom: 0.5rem;
}

.date {
  color: #666;
  font-style: italic;
  margin-bottom: 1rem;
}

/* Project Items */
.project-item {
  margin-bottom: 2.5rem;
  padding: 1.5rem;
  background: white;
  border-left: 4px solid #0f3460;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-item:hover {
  transform: translateX(10px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.project-item h3 {
  margin-top: 0;
  color: #1a1a2e;
  font-size: 1.5rem;
}

.advisors {
  color: #666;
  font-size: 0.95rem;
  margin-bottom: 1rem;
}

/* Skills Grid */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.skill-category {
  padding: 1.5rem;
  background: white;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.skill-category h3 {
  color: #1a1a2e;
  margin-top: 0;
  border-bottom: 2px solid #0f3460;
  padding-bottom: 0.5rem;
}

/* Publications */
.publication-item, .talk-item, .conference-item {
  margin-bottom: 1.5rem;
  padding: 1rem;
  background: white;
  border-left: 4px solid #0f3460;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Contact Form */
.contact-form {
  max-width: 600px;
  margin: 2rem auto;
}

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

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: #1a1a2e;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.75rem;
  border: 2px solid #ddd;
  border-radius: 4px;
  font-size: 1rem;
  transition: border-color 0.3s ease;
  box-sizing: border-box;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: #0f3460;
}

.submit-btn {
  background-color: #0f3460;
  color: white;
  padding: 1rem 2rem;
  border: none;
  border-radius: 4px;
  font-size: 1.1rem;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.submit-btn:hover {
  background-color: #1a1a2e;
}

/* Navigation Active State */
.active-nav-item a {
  color: #0f3460 !important;
  font-weight: 600;
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-subtitle {
    font-size: 1.2rem;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .skills-grid {
    grid-template-columns: 1fr;
  }
  
  .content-section {
    padding: 60px 0;
  }
}

/* Smooth Scrolling */
html {
  scroll-behavior: smooth;
}

/* Add padding to sections for navigation offset */
section {
  scroll-margin-top: 80px;
}