/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.5;
    color: #333;
    background-color: #fff;
    font-size: 14px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
}

h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: #2c3e50;
}

p {
    margin-bottom: 1rem;
    color: #555;
}

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

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #e0e0e0;
    z-index: 1000;
    padding: 0.75rem 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #555;
    font-weight: 600;
    font-size: 1rem;
    transition: color 0.3s ease;
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
}

.nav-link:hover,
.nav-link.active {
    color: #2c3e50;
    background-color: #f8f9fa;
}

/* Hero Section */
.hero {
    padding: 8rem 0 5rem;
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    min-height: 80vh;
    display: flex;
    align-items: center;
    position: relative;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="hero-grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="white" opacity="0.05"/><circle cx="75" cy="75" r="1" fill="white" opacity="0.05"/><circle cx="50" cy="10" r="0.5" fill="white" opacity="0.03"/><circle cx="10" cy="60" r="0.5" fill="white" opacity="0.03"/><circle cx="90" cy="40" r="0.5" fill="white" opacity="0.03"/></pattern></defs><rect width="100" height="100" fill="url(%23hero-grain)"/></svg>');
    opacity: 0.5;
}

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

.hero-content {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-image {
    text-align: center;
}

.hero-image img {
    width: 250px;
    height: 250px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid #fff;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.hero-text h1 {
    color: white;
    margin-bottom: 1.5rem;
    font-size: 3rem;
    font-weight: 700;
    text-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    letter-spacing: -1px;
}

.tagline {
    font-size: 1.8rem;
    color: #ecf0f1;
    font-weight: 500;
    margin-bottom: 2rem;
}

.hero-description {
    font-size: 1.4rem;
    color: #bdc3c7;
    margin-bottom: 3rem;
    line-height: 1.7;
}

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

.contact-link {
    display: inline-block;
    padding: 1rem 2rem;
    background-color: rgba(255, 255, 255, 0.1);
    color: white;
    text-decoration: none;
    border-radius: 12px;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
}

.contact-link:hover {
    background-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
    border-color: rgba(255, 255, 255, 0.3);
}

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

.section:nth-child(even) {
    background-color: #f8f9fa;
}

/* About Section */
.about-content {
    max-width: 800px;
}

.about-content p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
    line-height: 1.7;
    color: #555;
}

.about-content a {
    color: #3498db;
    text-decoration: none;
    font-weight: 500;
    border-bottom: 1px solid transparent;
    transition: all 0.3s ease;
}

.about-content a:hover {
    color: #2980b9;
    border-bottom-color: #2980b9;
}

.about-content em {
    font-style: italic;
    color: #666;
    font-weight: 500;
}

.cv-link {
    margin-top: 2rem;
}

.cv-link .btn {
    background-color: #2c3e50 !important;
    color: white !important;
    border: none !important;
}

.cv-link .btn:hover {
    background-color: #34495e !important;
    color: white !important;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background-color: #2c3e50;
    color: white;
}

.btn-primary:hover {
    background-color: #34495e;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(44, 62, 80, 0.3);
}

.btn-secondary {
    background-color: transparent;
    color: #2c3e50;
    border: 2px solid #2c3e50;
}

.btn-secondary:hover {
    background-color: #2c3e50;
    color: white;
}

/* Research Section */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.research-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.research-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.research-card h3 {
    color: #2c3e50;
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
    line-height: 1.3;
}

.research-meta {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 1rem;
    min-height: 1.5rem; /* Fixed height for meta section */
}

.research-date {
    font-size: 0.9rem;
    color: #666;
    font-weight: 400;
}

.research-institution {
    font-size: 0.85rem;
    color: #888;
    font-weight: 500;
    font-style: italic;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.research-card p:not(.research-institution) {
    margin-bottom: 1rem;
    font-size: 0.95rem;
    flex-grow: 1; /* Allow description to expand */
}

.research-links {
    display: flex;
    gap: 1rem;
    margin-top: auto; /* Push links to bottom */
    align-items: flex-end;
}

.research-links a {
    color: #2c3e50;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    height: 2.5rem; /* Fixed height for buttons */
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 80px;
}

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

/* Publications Section */
.publications-content {
    max-width: 900px;
}

.selected-publications {
    margin-bottom: 2rem;
}

.publication-item {
    background: white;
    padding: 1.5rem;
    margin-bottom: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    border-left: 4px solid #2c3e50;
}

.publication-title {
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.publication-authors {
    color: #7f8c8d;
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.publication-venue {
    color: #555;
    font-style: italic;
    margin-bottom: 0.5rem;
}

.publication-links {
    display: flex;
    gap: 1rem;
    margin-top: 0.5rem;
}

.publication-links a {
    color: #2c3e50;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
}

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

.publications-footer {
    text-align: center;
    margin-top: 2rem;
}

/* Contact Section */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    max-width: 800px;
}

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

.contact-item {
    font-size: 1.1rem;
}

.contact-item strong {
    color: #2c3e50;
}

.contact-item a {
    color: #2c3e50;
    text-decoration: none;
}

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

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

/* Footer */
.footer {
    background-color: #2c3e50;
    color: white;
    padding: 2rem 0;
    text-align: center;
}

.footer p {
    margin-bottom: 0.5rem;
    color: #bdc3c7;
}

.last-updated {
    font-size: 0.9rem;
    color: #95a5a6;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-container {
        flex-wrap: wrap;
        gap: 1rem;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }
    
    .hero-image {
        order: -1;
    }
    
    .hero-image img {
        width: 250px;
        height: 250px;
    }
    
    .hero-text h1 {
        font-size: 2.5rem;
    }
    
    .tagline {
        font-size: 1.4rem;
    }
    
    .hero-description {
        font-size: 1.1rem;
    }
    
    .hero-links {
        justify-content: center;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .research-grid {
        grid-template-columns: 1fr;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .hero {
        padding: 6rem 0 2rem;
    }
}

@media (max-width: 480px) {
    .hero-links {
        flex-direction: column;
        align-items: center;
    }
    
    .contact-link {
        width: 200px;
        text-align: center;
    }
    
    .news-item {
        flex-direction: column;
    }
    
    .news-date {
        margin-right: 0;
        margin-bottom: 0.5rem;
    }
    
    .interests-grid {
        gap: 2rem;
        margin-top: 2rem;
    }
    
    .interest-card {
        padding: 2rem;
    }
    
    .interest-card .interest-icon {
        font-size: 4.5rem !important;
    }
    
    .interest-card h3 {
        font-size: 2rem !important;
    }
    
    .interest-card p {
        font-size: 1.2rem !important;
    }
    
    .research-links {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .publication-links {
        flex-direction: column;
        gap: 0.5rem;
    }
}

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

/* Loading states */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* News Section */
.news-timeline {
    max-width: 800px;
    margin: 0 auto;
}

.news-item {
    display: flex;
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid #eee;
}

.news-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
}

.news-date {
    min-width: 90px;
    font-weight: 600;
    color: #2c3e50;
    font-size: 0.9rem;
    margin-right: 1.5rem;
}

.news-content {
    flex: 1;
}

.news-content h3 {
    color: #2c3e50;
    margin-bottom: 0.3rem;
    font-size: 1.1rem;
    line-height: 1.3;
}

.news-content p {
    color: #666;
    margin-bottom: 0.3rem;
    line-height: 1.5;
    font-size: 0.95rem;
}

.news-venue {
    font-style: italic;
    color: #888;
    font-size: 0.85rem;
    margin-bottom: 0.3rem;
}

.news-links {
    margin-top: 0.3rem;
}

.news-links a {
    display: inline-block;
    margin-right: 1rem;
    color: #3498db;
    text-decoration: none;
    font-size: 0.85rem;
}

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

/* Research Sections */
.research-section {
    margin-bottom: 3rem;
}

.research-section h3 {
    color: #2c3e50;
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    border-bottom: 2px solid #3498db;
    padding-bottom: 0.5rem;
}

.research-date {
    font-size: 0.9rem;
    color: #666;
    font-weight: 400;
}

.research-institution {
    font-size: 0.85rem;
    color: #888;
    font-weight: 500;
    font-style: italic;
    margin: -0.5rem 0 0.5rem 0;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Interests Section */
.interests-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    margin-top: 1.5rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.interest-card {
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    border-radius: 14px;
    padding: 1.5rem;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.06);
    text-align: left;
    transition: all 0.4s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
}

.interest-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #667eea, #764ba2, #f093fb);
}

.interest-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.interest-card:nth-child(1)::before {
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.interest-card:nth-child(2)::before {
    background: linear-gradient(90deg, #f093fb, #f5576c);
}

.interest-card:nth-child(3)::before {
    background: linear-gradient(90deg, #4facfe, #00f2fe);
}

.interest-card .interest-icon {
    font-size: 3rem !important;
    margin-bottom: 1rem !important;
    display: block !important;
    text-align: center !important;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.08)) !important;
}

.interest-card h3 {
    color: #2c3e50 !important;
    margin-bottom: 1rem !important;
    font-size: 1.6rem !important;
    font-weight: 700 !important;
    text-align: center !important;
    letter-spacing: -0.2px !important;
    line-height: 1.2 !important;
}

.interest-card p {
    color: #555 !important;
    line-height: 1.5 !important;
    font-size: 1rem !important;
    text-align: center !important;
    max-width: 550px !important;
    margin: 0 auto !important;
}

/* Focus states for accessibility */
.contact-link:focus,
.btn:focus,
.nav-link:focus {
    outline: 2px solid #2c3e50;
    outline-offset: 2px;
}