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

:root {
    --primary-color: #3b82f6;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --border-color: #e5e7eb;
    --link-color: #3b82f6;
    --link-hover: #2563eb;
    --transition: all 0.2s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.7;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    font-size: 16px;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 1rem 0;
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    transition: var(--transition);
}

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

/* About Section */
.about-section {
    padding-top: 100px;
    padding-bottom: 4rem;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 4rem;
    align-items: start;
}

.name-title {
    font-size: 3rem;
    font-weight: 400;
    margin-bottom: 2rem;
    line-height: 1.2;
}

.first-name {
    font-weight: 700;
}

.bio {
    color: var(--text-primary);
    margin-bottom: 2rem;
}

.bio p {
    margin-bottom: 1.25rem;
    line-height: 1.7;
}

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

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

.profile-image {
    position: sticky;
    top: 100px;
}

.profile-image img {
    width: 100%;
    border-radius: 50%;
    aspect-ratio: 1;
    object-fit: cover;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.social-icon {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 1.25rem;
    transition: var(--transition);
}

.social-icon:hover {
    color: var(--text-primary);
}

/* Research Overview Section */
.research-section {
    padding: 4rem 0;
    background-color: var(--bg-primary);
}

.research-intro {
    font-size: 1.05rem;
    color: var(--text-primary);
    margin-bottom: 2rem;
    text-align: center;
}

.research-pillars {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.research-pillar {
    background-color: var(--bg-secondary);
    padding: 1.75rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.research-pillar:hover {
    border-color: var(--primary-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.pillar-title {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    line-height: 1.3;
}

.pillar-content {
    color: var(--text-primary);
    line-height: 1.7;
    font-size: 0.95rem;
}

/* Publications Section */
.publications-section {
    padding: 4rem 0;
    background-color: var(--bg-secondary);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.section-title {
    font-size: 2rem;
    font-weight: 400;
    margin: 0;
}

.show-more-btn {
    padding: 0.5rem 1.5rem;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 2rem;
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition);
}

.show-more-btn:hover {
    border-color: var(--text-secondary);
}

.category-tabs {
    margin-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
}

.tab-btn {
    padding: 0.75rem 0;
    margin-right: 2rem;
    background: none;
    border: none;
    font-size: 0.95rem;
    color: var(--text-secondary);
    cursor: pointer;
    position: relative;
    transition: var(--transition);
}

.tab-btn.active {
    color: var(--text-primary);
    font-weight: 500;
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 2px;
    background-color: var(--text-primary);
}

.publications-list {
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
}

.publication-item {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 2rem;
    background-color: var(--bg-primary);
    padding: 1.5rem;
    border-radius: 0.5rem;
}

.publication-image img {
    width: 100%;
    height: auto;
    border-radius: 0.25rem;
    border: 1px solid var(--border-color);
    object-fit: contain;
}

.publication-title {
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.publication-authors {
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
    font-size: 0.95rem;
}

.author-link {
    color: var(--link-color);
    text-decoration: none;
}

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

.publication-venue {
    color: var(--text-secondary);
    font-style: italic;
    margin-bottom: 0.75rem;
    font-size: 0.95rem;
}

.publication-summary {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    font-size: 0.9rem;
    line-height: 1.6;
}

.publication-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.pub-link {
    padding: 0.35rem 0.85rem;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 0.25rem;
    text-decoration: none;
    color: var(--text-primary);
    font-size: 0.85rem;
    font-weight: 500;
    transition: var(--transition);
}

.pub-link:hover {
    border-color: var(--text-secondary);
}

/* Services Section */
.services-section {
    padding: 4rem 0;
    background-color: var(--bg-secondary);
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.service-card {
    background-color: var(--bg-primary);
    padding: 1.75rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.service-card:hover {
    border-color: var(--primary-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    transform: translateY(-2px);
}

.service-card-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    line-height: 1.3;
}

.service-card-content {
    color: var(--text-primary);
    line-height: 1.7;
    font-size: 0.95rem;
    flex-grow: 1;
    margin-bottom: 0.75rem;
}

.service-link {
    color: var(--link-color);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
    align-self: flex-start;
}

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



/* Footer */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    text-align: center;
    margin-top: 4rem;
}

.footer p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 900px) {
    .about-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .profile-image {
        order: -1;
        max-width: 250px;
        margin: 0 auto;
        position: static;
    }
    
    .research-pillars {
        grid-template-columns: 1fr;
    }
    
    .publication-item {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .publication-image {
        max-width: 280px;
    }
    
    .service-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .container {
        padding: 0 1.25rem;
    }
    
    .nav-container {
        padding: 0 1.25rem;
    }
    
    .nav-menu {
        gap: 1.25rem;
    }
    
    .name-title {
        font-size: 2.25rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .about-section {
        padding-top: 80px;
    }
}