/* =========================================
   CSS Variables - Easy Theme Customization
   ========================================= */
:root {
    /* Colors - Light Mode */
    --primary-color: #0066cc;
    --accent-color: #00509e;
    --text-primary: #1a1a1a;
    --text-secondary: #4a4a4a;
    --text-muted: #737373;
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --border-color: #dee2e6;
    --shadow: rgba(0, 0, 0, 0.1);
    --shadow-hover: rgba(0, 0, 0, 0.15);
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-serif: 'Merriweather', Georgia, serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    
    /* Transitions */
    --transition: all 0.3s ease;
}

/* Dark Mode Variables */
[data-theme="dark"] {
    --primary-color: #4da3ff;
    --accent-color: #6bb3ff;
    --text-primary: #e4e4e7;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    --bg-primary: #18181b;
    --bg-secondary: #27272a;
    --bg-tertiary: #3f3f46;
    --border-color: #52525b;
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-hover: rgba(0, 0, 0, 0.4);
}

/* =========================================
   Base Styles
   ========================================= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* =========================================
   Navigation
   ========================================= */
.navbar {
    position: sticky;
    top: 0;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: 0 2px 10px var(--shadow);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
}

.logo {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.logo:hover {
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 0;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-secondary);
    padding: 0.5rem;
    display: flex;
    align-items: center;
    transition: var(--transition);
}

.theme-toggle:hover {
    color: var(--primary-color);
}

.theme-toggle .sun-icon {
    display: none;
}

.theme-toggle .moon-icon {
    display: block;
}

[data-theme="dark"] .theme-toggle .sun-icon {
    display: block;
}

[data-theme="dark"] .theme-toggle .moon-icon {
    display: none;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 3px 0;
    transition: var(--transition);
}

/* =========================================
   Hero Section
   ========================================= */
.hero {
    padding: var(--spacing-xl) 0;
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.hero-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

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

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.hero-links {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.hero-meta {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.meta-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-muted);
    font-size: 0.9rem;
}

.meta-item svg {
    flex-shrink: 0;
}

.profile-image {
    width: 100%;
    max-width: 400px;
    height: auto;
    border-radius: var(--radius-lg);
    box-shadow: 0 10px 40px var(--shadow);
    transition: var(--transition);
}

.profile-image:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 50px var(--shadow-hover);
}

.hero-image {
    position: relative;
}

.social-links {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
    justify-content: center;
}

.social-links a {
    color: var(--text-secondary);
    transition: var(--transition);
    padding: 0.5rem;
    border-radius: var(--radius-sm);
}

.social-links a:hover {
    color: var(--primary-color);
    background-color: var(--bg-tertiary);
}

/* =========================================
   Buttons
   ========================================= */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    border: 2px solid transparent;
    cursor: pointer;
}

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

.btn-primary:hover {
    background-color: var(--accent-color);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px var(--shadow);
}

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

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

/* =========================================
   Sections
   ========================================= */
.section {
    padding: var(--spacing-xl) 0;
}

.section-alt {
    background-color: var(--bg-secondary);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
    text-align: center;
    color: var(--text-primary);
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background-color: var(--primary-color);
    margin: var(--spacing-sm) auto 0;
    border-radius: 2px;
}

/* =========================================
   Prose Content
   ========================================= */
.prose {
    max-width: 800px;
    margin: 0 auto;
}

.prose h3 {
    font-size: 1.75rem;
    margin: var(--spacing-md) 0 var(--spacing-sm);
    color: var(--text-primary);
}

.prose h4 {
    font-size: 1.25rem;
    margin: var(--spacing-sm) 0;
    color: var(--primary-color);
}

.prose p {
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
    line-height: 1.8;
}

.prose a {
    color: var(--primary-color);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.prose a:hover {
    border-bottom-color: var(--primary-color);
}

.prose ul, .prose ol {
    margin: var(--spacing-sm) 0;
    padding-left: var(--spacing-md);
    color: var(--text-secondary);
}

.prose li {
    margin-bottom: 0.5rem;
}

/* =========================================
   Research Grid
   ========================================= */
.research-grid {
    display: grid;
    gap: var(--spacing-md);
}

.research-card {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
}

.research-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px var(--shadow-hover);
}

.research-card h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
    font-size: 1.5rem;
}

.research-card p {
    color: var(--text-secondary);
    line-height: 1.8;
}

.research-projects {
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-sm);
    border-top: 1px solid var(--border-color);
}

.research-projects strong {
    color: var(--text-primary);
}

.research-projects a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

.research-projects a:hover {
    text-decoration: underline;
}

/* =========================================
   Publications
   ========================================= */
.publications-controls {
    margin-bottom: var(--spacing-md);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.search-box input {
    width: 100%;
    padding: 0.75rem var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition);
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

.filter-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.filter-btn {
    padding: 0.5rem var(--spacing-sm);
    border: 1px solid var(--border-color);
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

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

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

.publications-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.publication-item {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
}

.publication-item:hover {
    box-shadow: 0 5px 20px var(--shadow-hover);
}

.publication-year {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.publication-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.publication-authors {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
    font-size: 0.95rem;
}

.publication-journal {
    color: var(--text-muted);
    font-style: italic;
    margin-bottom: var(--spacing-sm);
    font-size: 0.9rem;
}

.publication-links {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.publication-link {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.25rem 0.75rem;
    background-color: var(--bg-tertiary);
    color: var(--primary-color);
    text-decoration: none;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    transition: var(--transition);
}

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

.loading-spinner {
    text-align: center;
    padding: var(--spacing-lg);
}

.spinner {
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-sm);
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* =========================================
   Projects
   ========================================= */
.projects-filter {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    margin-bottom: var(--spacing-md);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: var(--spacing-md);
}

.project-card {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
    border-left: 4px solid var(--primary-color);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px var(--shadow-hover);
}

.project-card h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    font-size: 1.25rem;
}

.project-meta {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    flex-wrap: wrap;
}

.project-card p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* =========================================
   News Grid
   ========================================= */
.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.news-item {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
}

.news-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px var(--shadow-hover);
}

.news-date {
    color: var(--primary-color);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.news-item h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    font-size: 1.125rem;
}

.news-item p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* =========================================
   Contact
   ========================================= */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
}

.contact-info h3 {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.contact-details {
    margin-top: var(--spacing-md);
}

.contact-item {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.contact-item svg {
    color: var(--primary-color);
    flex-shrink: 0;
    margin-top: 0.25rem;
}

.contact-item strong {
    display: block;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.contact-item p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.contact-item a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

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

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: 1rem;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

.form-note {
    font-size: 0.85rem;
    color: var(--text-muted);
    text-align: center;
    margin-top: var(--spacing-xs);
}

/* =========================================
   Page Headers
   ========================================= */
.page-header {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
    padding: var(--spacing-lg) 0;
    text-align: center;
}

.page-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

.page-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
}

/* =========================================
   People / Team Pages
   ========================================= */
.people-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: var(--spacing-md);
}

.person-card {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
}

.person-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px var(--shadow-hover);
}

.person-photo-link {
    display: block;
    text-decoration: none;
}

.person-photo {
    width: 100%;
    height: 250px;
    overflow: hidden;
    background-color: var(--bg-tertiary);
}

.person-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.person-card:hover .person-photo img {
    transform: scale(1.05);
}

.person-info {
    padding: var(--spacing-md);
}

.person-info h3 {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
}

.person-name-link {
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.person-name-link:hover {
    color: var(--primary-color);
}

.person-role {
    color: var(--primary-color);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.person-affiliation {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: 0.25rem;
}

.person-links {
    margin-top: var(--spacing-sm);
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.person-links a {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.person-links a:hover {
    text-decoration: underline;
}

/* Alumni Styles */
.alumni-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.alumni-card {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    display: grid;
    grid-template-columns: 150px 1fr;
    gap: var(--spacing-md);
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
}

.alumni-card:hover {
    box-shadow: 0 5px 20px var(--shadow-hover);
}

.alumni-photo {
    width: 150px;
    height: 150px;
    border-radius: var(--radius-md);
    overflow: hidden;
    background-color: var(--bg-tertiary);
}

.alumni-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.alumni-info h3 {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.alumni-degree {
    color: var(--primary-color);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.alumni-thesis {
    color: var(--text-secondary);
    font-style: italic;
    margin-bottom: 0.5rem;
    line-height: 1.5;
}

.alumni-institution {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.alumni-current {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-top: 0.5rem;
}

@media (max-width: 768px) {
    .alumni-card {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .alumni-photo {
        margin: 0 auto;
    }
    
    .people-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
}

/* =========================================
   Publications
   ========================================= */

/* Year Grouping */
.year-group {
    margin-bottom: var(--spacing-md);
}

.year-header {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

.year-publications {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

/* Individual Publication Item */
.publication-item {
    padding-bottom: var(--spacing-sm);
}

.pub-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.pub-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.pub-authors {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.25rem;
}

.pub-meta {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.pub-date::after {
    content: " • ";
    margin: 0 0.25rem;
}

.pub-venue {
    font-style: italic;
}

/* Publication Links */
.publication-item {
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

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

.pub-title {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.pub-meta {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.pub-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-bottom: 0.75rem;
}

.pub-tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.85rem;
    border-radius: var(--radius-sm);
    font-weight: 500;
}

.keyword-tag {
    background-color: var(--bg-secondary);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

.project-tag {
    background-color: #e8f5e9;
    color: #2e7d32;
    border: 1px solid #4caf50;
}

.pub-links {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.pub-link {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.pub-link:hover {
    text-decoration: underline;
}

.pub-link:not(:last-child)::after {
    content: "";
    margin-left: var(--spacing-sm);
}

/* Publications Controls */
.publications-controls {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    align-items: flex-start;
    flex-direction: column;
}

.search-box {
    width: 100%;
    min-width: 200px;
}

.search-box input {
    width: 100%;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1rem;
}

/* Theme Filters */
.theme-filters {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    width: 100%;
}

.theme-filter-btn {
    padding: 0.6rem 1.25rem;
    border: 2px solid var(--border-color);
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.theme-filter-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background-color: var(--bg-secondary);
}

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

.filter-buttons {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition);
}

.filter-btn:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

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

.publications-list {
    min-height: 200px;
}

.loading-spinner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: var(--spacing-md);
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* =========================================
   Biography Page
   ========================================= */
.biography-content {
    max-width: 900px;
    margin: 0 auto;
}

.biography-content > p {
    color: var(--text-secondary);
    line-height: 1.9;
    margin-bottom: var(--spacing-lg);
    font-size: 1.1rem;
}

.biography-content h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-top: 3rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

.biography-content h2:first-of-type {
    margin-top: 2rem;
}

.bio-table {
    width: 100%;
    margin-bottom: 2rem;
    border-collapse: collapse;
}

.bio-table tr {
    border-bottom: 1px solid rgba(0,0,0,0.06);
}

.bio-table tr:last-child {
    border-bottom: none;
}

.bio-table td {
    padding: 0.6rem 0;
    vertical-align: top;
}

.bio-years {
    width: 130px;
    min-width: 130px;
    color: var(--primary-color);
    font-size: 0.95rem;
    font-weight: 600;
    white-space: nowrap;
    padding-right: 2rem;
}

.bio-details {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 1.05rem;
}

.bio-details strong {
    color: var(--text-primary);
    font-weight: 600;
}

.bio-details em {
    color: var(--text-muted);
    font-style: italic;
    display: block;
    margin-top: 0.25rem;
    font-size: 0.95rem;
}

.bio-details br + strong {
    display: inline-block;
    margin-top: 0.25rem;
}

@media (max-width: 768px) {
    .biography-content {
        max-width: 100%;
    }
    
    .bio-table tr {
        display: flex;
        flex-direction: column;
        margin-bottom: 1.5rem;
        padding-bottom: 1.5rem;
    }
    
    .bio-table td {
        padding: 0.25rem 0;
        width: 100%;
    }
    
    .bio-years {
        width: 100%;
        margin-bottom: 0.5rem;
        font-size: 1rem;
    }
}

/* =========================================
   Research Cards with Images
   ========================================= */
.research-grid-with-images {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.research-card-with-image {
    display: grid;
    grid-template-columns: 350px 1fr;
    gap: var(--spacing-lg);
    background-color: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 10px var(--shadow);
}

.research-image {
    width: 100%;
    height: 250px;
    border-radius: var(--radius-md);
    overflow: hidden;
    background-color: var(--bg-tertiary);
}

.research-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.research-text h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.research-text p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

@media (max-width: 968px) {
    .research-card-with-image {
        grid-template-columns: 1fr;
    }
    
    .research-image {
        height: 200px;
    }
}

/* =========================================
   Fieldwork Page
   ========================================= */
.fieldwork-content {
    max-width: 900px;
    margin: 0 auto;
}

.fieldwork-intro {
    background-color: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-xl);
}

.fieldwork-intro p {
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 1.05rem;
    margin: 0;
}

.fieldwork-region-title {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-top: 3rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

.fieldwork-region-title:first-of-type {
    margin-top: 2rem;
}

.expedition-card {
    background-color: var(--bg-primary);
    border-left: 4px solid var(--primary-color);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border-radius: var(--radius-md);
    box-shadow: 0 2px 8px var(--shadow);
}

.expedition-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 0.75rem;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.expedition-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.expedition-date {
    color: var(--primary-color);
    font-weight: 500;
    font-size: 0.95rem;
}

.expedition-card p {
    color: var(--text-secondary);
    line-height: 1.7;
    margin: 0;
}

.expedition-card strong {
    color: var(--text-primary);
}

.expedition-card a {
    color: var(--primary-color);
    text-decoration: none;
}

.expedition-card a:hover {
    text-decoration: underline;
}

.expedition-gallery-link {
    display: inline-block;
    margin-top: 0.75rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-color);
    text-decoration: none;
}

.expedition-gallery-link:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .expedition-header {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* =========================================
   Projects List Page
   ========================================= */
.projects-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.project-card-list {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 2px 10px var(--shadow);
    transition: var(--transition);
}

.project-card-list:hover {
    box-shadow: 0 5px 20px var(--shadow-hover);
    transform: translateY(-2px);
}

.project-card-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.project-card-content h3 a {
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.project-card-content h3 a:hover {
    color: var(--primary-color);
}

.project-subtitle {
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-bottom: 0.5rem;
    font-style: italic;
}

.project-meta {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 0.75rem;
}

.project-description-short {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 1rem;
}

/* =========================================
   Project Pages
   ========================================= */
.breadcrumb {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.breadcrumb a {
    color: var(--primary-color);
    text-decoration: none;
}

.breadcrumb a:hover {
    text-decoration: underline;
}

.project-page-content {
    max-width: 900px;
    margin: 0 auto;
}

.project-meta-bar {
    display: flex;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
    padding: var(--spacing-md);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-xl);
}

.project-meta-bar .meta-item {
    font-size: 0.95rem;
}

.project-meta-bar .meta-item strong {
    color: var(--text-primary);
    margin-right: 0.25rem;
}

.project-website-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.project-website-link:hover {
    text-decoration: underline;
}

.project-description h2,
.project-team h2,
.project-publications h2,
.project-photos h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

/* Summary paragraph injected from JSON */
.project-summary {
    font-size: 1.05rem;
    line-height: 1.75;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

/* Fieldwork album cards on project pages */
.fieldwork-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.fieldwork-card {
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.fieldwork-card:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.10);
    transform: translateY(-2px);
}

.fieldwork-card-cover {
    aspect-ratio: 4/3;
    overflow: hidden;
    background: var(--bg-secondary);
}

.fieldwork-card-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.fieldwork-card-info {
    padding: var(--spacing-sm) var(--spacing-md);
}

.fieldwork-card-info strong {
    display: block;
    font-size: 0.95rem;
    color: var(--text-primary);
}

.fieldwork-card-info span {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.fieldwork-card-info p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin: 0.25rem 0 0;
}

.project-description p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
    font-size: 1.05rem;
}

/* Team Grid - Small version for project pages */
.team-grid-small {
    margin-top: var(--spacing-sm);
}

.team-role-section {
    margin-bottom: var(--spacing-md);
}

.team-role-section h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-sm);
}

.team-members {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: var(--spacing-md);
}

.team-member-mini {
    text-align: center;
}

.team-member-mini img {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 0.5rem;
    border: 2px solid var(--border-color);
}

.team-member-mini p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0;
}

/* Compact publication list for project pages */
.publications-list-compact {
    margin-top: var(--spacing-md);
}

.pub-item-compact {
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--border-color);
}

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

.pub-item-compact h4 {
    font-size: 1.05rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
    line-height: 1.4;
}

.pub-meta-compact {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.pub-link-compact {
    font-size: 0.9rem;
    color: var(--primary-color);
    text-decoration: none;
}

.pub-link-compact:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .project-meta-bar {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .team-members {
        grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    }
    
    .team-member-mini img {
        width: 80px;
        height: 80px;
    }
}

/* =========================================
   Contact Simple (for home page)
   ========================================= */
.contact-simple {
    display: flex;
    gap: var(--spacing-xl);
    justify-content: center;
}

.contact-simple .contact-item {
    text-align: center;
}

.contact-simple .contact-item strong {
    display: block;
    color: var(--text-primary);
    font-size: 1.125rem;
    margin-bottom: 0.5rem;
}

.contact-simple .contact-item p {
    color: var(--text-secondary);
    margin: 0;
}

@media (max-width: 768px) {
    .contact-simple {
        flex-direction: column;
        gap: var(--spacing-md);
    }
}

/* =========================================
   Research Cards
   ========================================= */
.research-grid {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.research-card {
    background-color: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 10px var(--shadow);
}

.research-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.research-card p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

.research-projects {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.research-projects p {
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.research-projects a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

.research-projects a:hover {
    text-decoration: underline;
}

/* =========================================
   Contact Page
   ========================================= */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
}

.contact-info h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
}

.contact-details {
    margin-top: var(--spacing-lg);
}

.contact-item {
    margin-bottom: var(--spacing-md);
}

.contact-item strong {
    display: block;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.contact-item p {
    color: var(--text-secondary);
    margin: 0;
}

.contact-form {
    background-color: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 10px var(--shadow);
}

.form-group {
    margin-bottom: var(--spacing-md);
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
}

.form-group textarea {
    resize: vertical;
}

.form-note {
    margin-top: var(--spacing-sm);
    font-size: 0.85rem;
    color: var(--text-muted);
}

@media (max-width: 768px) {
    .contact-grid {
        grid-template-columns: 1fr;
    }
}

/* =========================================
   Footer
   ========================================= */
.footer {
    background-color: var(--bg-secondary);
    padding: var(--spacing-lg) 0 var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.footer-section h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    font-size: 1.125rem;
}

.footer-section p,
.footer-section li {
    color: var(--text-secondary);
    line-height: 1.8;
}

.footer-section ul {
    list-style: none;
}

.footer-section a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--primary-color);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer-bottom p {
    margin: 0.25rem 0;
}

/* =========================================
   Responsive Design
   ========================================= */
@media (max-width: 968px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-image {
        order: -1;
    }
    
    .profile-image {
        max-width: 300px;
        margin: 0 auto;
    }
    
    .hero-links {
        justify-content: center;
    }
    
    .hero-meta {
        align-items: center;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 60px;
        flex-direction: column;
        background-color: var(--bg-primary);
        width: 100%;
        border-right: 1px solid var(--border-color);
        padding: var(--spacing-md);
        transition: left 0.3s ease;
        box-shadow: 0 5px 20px var(--shadow);
        align-items: flex-start;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(-45deg) translate(-5px, 6px);
    }
    
    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(45deg) translate(-5px, -6px);
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.25rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .section {
        padding: var(--spacing-lg) 0;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .hero {
        padding: var(--spacing-lg) 0;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .hero-links {
        flex-direction: column;
    }
    
    .filter-buttons {
        flex-direction: column;
    }
}

/* =========================================
   Print Styles
   ========================================= */
@media print {
    .navbar,
    .theme-toggle,
    .mobile-menu-toggle,
    .hero-links,
    .social-links,
    .contact-form,
    .footer {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .section {
        page-break-inside: avoid;
    }
}

/* Keyword Filter Buttons */
.keyword-filters {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
}

.keyword-btn {
    padding: 0.5rem 1rem;
    border: 2px solid var(--border-color);
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.keyword-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background-color: var(--bg-secondary);
}

.keyword-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* Publications List Compact Style */
.publications-list-compact {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.pub-item-compact {
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

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

.pub-item-compact h4 {
    font-size: 1.05rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.pub-meta-compact {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.pub-link-compact {
    display: inline-block;
    color: var(--primary-color);
    font-size: 0.9rem;
    text-decoration: none;
    transition: var(--transition);
}

.pub-link-compact:hover {
    text-decoration: underline;
}

/* Research Theme Pages */
.theme-page-content {
    max-width: 900px;
}

.theme-description {
    margin-bottom: var(--spacing-xl);
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--text-primary);
}

.theme-projects {
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-lg);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border-left: 4px solid var(--primary-color);
}

.theme-projects h2 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.theme-projects p {
    margin-bottom: var(--spacing-sm);
    line-height: 1.6;
}

.theme-projects a {
    color: #0066cc;
    text-decoration: none;
    transition: var(--transition);
}

.theme-projects a:hover {
    color: #0052a3;
    text-decoration: underline;
}

.theme-publications-full h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--border-color);
}

/* Better link colors throughout */
a {
    color: #0066cc;
}

a:hover {
    color: #0052a3;
}

.pub-link-compact {
    color: #0066cc !important;
}

.pub-link-compact:hover {
    color: #0052a3 !important;
}

/* DOI Link Styling */
.doi-link {
    color: #0066cc !important;
    text-decoration: none;
    transition: var(--transition);
}

.doi-link:hover {
    color: #0052a3 !important;
    text-decoration: underline;
}