@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Space+Grotesk:wght@400;500;600;700&display=swap');

:root {
    --bg-primary: #fafafa;
    --bg-secondary: #ffffff;
    --text-primary: #0a0a0a;
    --text-secondary: #525252;
    --text-tertiary: #737373;
    --accent: #171717;
    --accent-hover: #404040;
    --border: #e5e5e5;
    --subtle-accent: #f5f5f5;
}

[data-theme="dark"] {
    --bg-primary: #0a0a0a;
    --bg-secondary: #171717;
    --text-primary: #fafafa;
    --text-secondary: #a3a3a3;
    --text-tertiary: #737373;
    --accent: #fafafa;
    --accent-hover: #d4d4d4;
    --border: #262626;
    --subtle-accent: #1a1a1a;
}

* {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    font-weight: 600;
    letter-spacing: -0.02em;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
    font-size: 15px;
    line-height: 1.6;
}

.bg-gradient-subtle {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.section-container {
    max-width: 960px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
}

.section-title {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: 2rem;
    color: var(--text-primary);
    letter-spacing: -0.03em;
}

.narrative-text {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    padding: 1.5rem;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.card:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.03);
    border-color: var(--text-tertiary);
}

.btn-primary {
    background-color: var(--accent);
    color: var(--bg-primary);
    padding: 0.625rem 1.25rem;
    border-radius: 0.375rem;
    text-decoration: none;
    display: inline-block;
    transition: all 0.2s ease;
    font-weight: 500;
    font-size: 0.9rem;
    letter-spacing: -0.01em;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.link-accent {
    color: var(--text-primary);
    text-decoration: none;
    border-bottom: 1px solid var(--border);
    transition: border-color 0.2s ease;
    font-weight: 500;
}

.link-accent:hover {
    border-bottom-color: var(--text-primary);
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
    font-size: 0.9rem;
    font-weight: 500;
}

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

.nav-link.active {
    color: var(--text-primary);
    font-weight: 600;
}

/* Side Navigation for Desktop */
.side-nav {
    position: fixed;
    left: 0;
    top: 0;
    height: 100vh;
    width: 220px;
    background-color: var(--bg-primary);
    border-right: 1px solid var(--border);
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    z-index: 50;
}

.side-nav-header {
    margin-bottom: 2rem;
}

.side-nav-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.side-nav-links {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    flex: 1;
}

.side-nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 500;
}

.side-nav-link i {
    width: 1.25rem;
    text-align: center;
    font-size: 0.9rem;
}

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

.side-nav-link.active {
    color: var(--text-primary);
    font-weight: 600;
}

.side-nav-footer {
    border-top: 1px solid var(--border);
    padding-top: 1rem;
    margin-top: auto;
}

.footer-icons {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.footer-icon-link {
    background-color: var(--subtle-accent);
    border: 1px solid var(--border);
    border-radius: 0.375rem;
    padding: 0.5rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    width: 2.5rem;
    height: 2.5rem;
    color: var(--text-secondary);
    text-decoration: none;
}

.footer-icon-link:hover {
    background-color: var(--border);
    color: var(--text-primary);
    transform: translateY(-1px);
}

.footer-icon-link i {
    font-size: 1rem;
}

.footer-text {
    text-align: center;
    color: var(--text-tertiary);
    font-size: 0.75rem;
    line-height: 1.5;
    opacity: 0.9;
}

.side-nav-contact {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.side-nav-contact a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.2s ease;
}

.side-nav-contact a i {
    width: 1.25rem;
    text-align: center;
}

.side-nav-contact a:hover {
    color: var(--text-primary);
}

.main-content-with-sidebar {
    margin-left: 220px;
}

.top-nav {
    display: none;
}

/* Mobile: Top Navigation */
@media (max-width: 1024px) {
    .side-nav {
        display: none;
    }
    
    .top-nav {
        display: block;
    }
    
    .main-content-with-sidebar {
        margin-left: 0;
    }
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    overflow-y: auto;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: var(--bg-primary);
    border-radius: 0.75rem;
    max-width: 800px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    padding: 2rem;
    position: relative;
    border: 1px solid var(--border);
}

.theme-toggle {
    background-color: var(--subtle-accent);
    border: 1px solid var(--border);
    border-radius: 0.375rem;
    padding: 0.5rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    width: fit-content;
}

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

.theme-icon {
    font-size: 1.125rem;
    color: var(--text-secondary);
    transition: transform 0.3s ease;
}

/* Show moon icon in light mode (click to go to dark) */
[data-theme="light"] .theme-icon::before {
    content: "\f186"; /* fa-moon */
    font-family: "Font Awesome 6 Free";
    font-weight: 900;
}

/* Show sun icon in dark mode (click to go to light) */
[data-theme="dark"] .theme-icon::before {
    content: "\f185"; /* fa-sun */
    font-family: "Font Awesome 6 Free";
    font-weight: 900;
}

.theme-toggle-mobile {
    background-color: transparent;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: color 0.2s ease;
}

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

/* Mobile icon navigation */
.nav-link-icon {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
    padding: 0.5rem;
    font-size: 1.125rem;
}

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

.tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background-color: var(--subtle-accent);
    border: 1px solid var(--border);
    border-radius: 9999px;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-right: 0.5rem;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.avatar {
    width: 80px;
    height: 80px;
    border-radius: 0.375rem;
    object-fit: cover;
    border: 1px solid var(--border);
}

.search-input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border);
    border-radius: 0.375rem;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-weight: 400;
}

.search-input:focus {
    outline: none;
    border-color: var(--text-tertiary);
}

.hero-section {
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 6rem 1.5rem 4rem;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
    letter-spacing: -0.03em;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-weight: 400;
}

/* Academic Homepage Styles */
.academic-header {
    margin-bottom: 2rem;
}

.about-with-image {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
}

.about-text-wrapper {
    flex: 1;
}

.profile-photo {
    width: 180px;
    height: 180px;
    border-radius: 0.375rem;
    object-fit: cover;
    border: 1px solid var(--border);
    flex-shrink: 0;
    float: right;
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.header-info {
    flex: 1;
}

.name-title {
    font-size: 1.875rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    letter-spacing: -0.03em;
}

.affiliation {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-weight: 400;
}

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

.simple-section {
    margin-bottom: 3rem;
}

.simple-section-title {
    font-size: 1.375rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border);
    padding-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.publication-item {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
    position: relative;
}

.publication-item::before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--text-secondary);
    font-weight: bold;
}

.pub-title {
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

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

.pub-venue {
    font-size: 0.85rem;
    color: var(--text-tertiary);
    font-style: italic;
}

.pub-links {
    display: inline-flex;
    gap: 0.75rem;
    margin-left: 0.5rem;
    font-size: 0.85rem;
}

/* Project Card Styles */
.project-card {
    padding: 0;
    overflow: hidden;
}

.project-layout {
    display: flex;
    gap: 1.5rem;
    align-items: stretch;
}

.project-media {
    flex: 0 0 300px;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--subtle-accent);
}

.project-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.project-info {
    flex: 1;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
}

.project-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.project-tldr {
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    flex: 1;
}

.read-more-btn {
    background-color: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border);
    padding: 0.625rem 1.25rem;
    border-radius: 0.375rem;
    cursor: pointer;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    width: fit-content;
}

.read-more-btn:hover {
    background-color: var(--accent);
    color: var(--bg-primary);
    border-color: var(--accent);
    transform: translateY(-1px);
}

.read-more-btn i {
    font-size: 0.75rem;
    transition: transform 0.2s ease;
}

.read-more-btn:hover i {
    transform: translateX(3px);
}

.modal-close {
    transition: all 0.2s ease;
}

.modal-close:hover {
    color: var(--text-primary) !important;
    transform: scale(1.1);
}

@media (max-width: 768px) {
    .section-title {
        font-size: 1.5rem;
    }
    
    .narrative-text {
        font-size: 0.95rem;
    }
    
    .section-container {
        padding: 3rem 1rem;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.125rem;
    }
    
    .academic-header {
        text-align: center;
    }
    
    .about-with-image {
        flex-direction: column;
    }
    
    .profile-photo {
        float: none;
        margin: 0 auto 1rem;
        width: 150px;
        height: 150px;
    }
    
    .about-text-wrapper {
        text-align: left;
    }
    
    .contact-links {
        justify-content: center;
    }
    
    .name-title {
        font-size: 1.5rem;
    }
    
    /* Project card responsive */
    .project-layout {
        flex-direction: column;
    }
    
    .project-media {
        flex: 0 0 auto;
        width: 100%;
        min-height: 180px;
    }
    
    .project-title {
        font-size: 1.25rem;
    }
}