/* Professional Academic Website Styles */

:root {
  --primary-color: #2c3e50;
  --secondary-color: #3498db;
  --accent-color: #e74c3c;
  --light-gray: #f8f9fa;
  --medium-gray: #e9ecef;
  --dark-gray: #6c757d;
  --text-color: #2c3e50;
  --border-color: #dee2e6;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, monospace;
}

/* Typography */
body {
  font-family: var(--font-sans);
  color: var(--text-color);
  line-height: 1.6;
  font-weight: 400;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: 1rem;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

/* Navigation */
.navbar {
  background-color: white;
  border-bottom: 1px solid var(--border-color);
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar-brand {
  font-weight: 600;
  color: var(--primary-color) !important;
}

.nav-link {
  font-weight: 500;
  color: var(--text-color) !important;
  transition: color 0.2s ease;
}

.nav-link:hover {
  color: var(--secondary-color) !important;
}

/* Hero Section */
.hero-section {
  padding: 4rem 0;
  background: linear-gradient(135deg, var(--light-gray) 0%, white 100%);
  border-bottom: 1px solid var(--border-color);
}

.hero-title {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--primary-color);
}

.hero-subtitle {
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--dark-gray);
  margin-bottom: 1.5rem;
}

.profile-image {
  width: 180px;
  height: 180px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--secondary-color);
  box-shadow: 0 8px 25px rgba(52, 152, 219, 0.3);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.profile-image:hover {
  transform: scale(1.05);
  box-shadow: 0 12px 35px rgba(52, 152, 219, 0.4);
}

/* Content Sections */
.content-section {
  padding: 4rem 0;
}

.content-section.bg-light {
  background-color: var(--light-gray);
}

.section-title {
  font-size: 2.25rem;
  font-weight: 600;
  text-align: center;
  margin-bottom: 3rem;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--secondary-color), var(--accent-color));
  border-radius: 2px;
}

/* Publication Items */
.publication-item {
  background: white;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  border-radius: 8px;
  border-left: 4px solid var(--secondary-color);
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.publication-item:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

.publication-item h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--primary-color);
}

.publication-item p {
  color: var(--dark-gray);
  margin-bottom: 0.75rem;
  font-size: 0.9rem;
}

.publication-link {
  color: var(--secondary-color);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.publication-link:hover {
  color: var(--primary-color);
  text-decoration: underline;
}

/* Author Highlight */
.author-highlight {
  color: var(--accent-color);
  font-weight: 700;
  background: linear-gradient(120deg, rgba(231, 76, 60, 0.1) 0%, rgba(231, 76, 60, 0.05) 100%);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  border-left: 3px solid var(--accent-color);
}

/* Tool Items */
.tool-item {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  height: 100%;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.tool-item:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

.tool-item h3 {
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.tool-item p {
  color: var(--dark-gray);
  margin-bottom: 1rem;
}

.tool-link {
  color: var(--secondary-color);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.tool-link:hover {
  color: var(--primary-color);
  text-decoration: underline;
}

/* Project Items */
.project-item {
  background: white;
  padding: 2rem;
  margin-bottom: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  border-top: 4px solid var(--secondary-color);
}

.project-item h3 {
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.project-item p {
  margin-bottom: 0.5rem;
  color: var(--dark-gray);
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 500;
  text-decoration: none;
  display: inline-block;
  transition: all 0.2s ease;
  border: none;
  cursor: pointer;
}

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

.btn-primary:hover {
  background-color: #2980b9;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(52, 152, 219, 0.4);
}

.btn-outline-primary {
  background-color: transparent;
  color: var(--secondary-color);
  border: 2px solid var(--secondary-color);
}

.btn-outline-primary:hover {
  background-color: var(--secondary-color);
  color: white;
  transform: translateY(-1px);
}

/* Footer */
.page-footer {
  background-color: var(--primary-color);
  color: white;
  padding: 3rem 0;
  margin-top: 4rem;
  text-align: center;
}

.page-footer a {
  color: white;
  margin: 0 0.75rem;
  font-size: 1.5rem;
  transition: color 0.2s ease;
}

.page-footer a:hover {
  color: var(--secondary-color);
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-subtitle {
    font-size: 1.25rem;
  }
  
  .profile-image {
    width: 150px;
    height: 150px;
  }
  
  .content-section {
    padding: 2rem 0;
  }
  
  .section-title {
    font-size: 1.75rem;
  }
}

@media (max-width: 576px) {
  .hero-section {
    padding: 2rem 0;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .profile-image {
    width: 120px;
    height: 120px;
  }
}

/* Utility Classes */
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }

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

/* Focus states for accessibility */
a:focus,
button:focus {
  outline: 2px solid var(--secondary-color);
  outline-offset: 2px;
}