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

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #64748b;
    --accent-color: #f59e0b;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-light: #94a3b8;
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --border-radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
}

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

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

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-line {
    width: 80px;
    height: 4px;
    background: var(--gradient-primary);
    margin: 0 auto 3rem;
    border-radius: 2px;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo .logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition);
}

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

.nav-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.theme-toggle {
    background: none;
    border: none;
    font-size: 1.2rem;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: var(--transition);
}

.theme-toggle:hover {
    background: var(--bg-secondary);
    transform: scale(1.1);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    transition: var(--transition);
    border-radius: 2px;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    position: relative;
    overflow: hidden;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.title-line {
    display: block;
    line-height: 1.1;
}

.title-line.highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

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

.btn {
    display: inline-block;
    padding: 1rem 2rem;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

.hero-visual {
    position: relative;
    height: 400px;
}

.floating-elements {
    position: relative;
    width: 100%;
    height: 100%;
}

.floating-element {
    position: absolute;
    width: 100px;
    height: 100px;
    background: var(--gradient-secondary);
    border-radius: 50%;
    opacity: 0.1;
    animation: float 6s ease-in-out infinite;
}

.floating-element:nth-child(1) {
    top: 20%;
    left: 20%;
    animation-delay: 0s;
}

.floating-element:nth-child(2) {
    top: 60%;
    right: 20%;
    animation-delay: 2s;
}

.floating-element:nth-child(3) {
    bottom: 20%;
    left: 50%;
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(180deg); }
}

/* Sections */
.section {
    padding: 6rem 0;
}

.section:nth-child(even) {
    background: var(--bg-secondary);
}

/* About Section */
.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.8;
}

.about-details {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-tertiary);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.detail-item:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-md);
}

.detail-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.about-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.image-placeholder {
    width: 200px;
    height: 200px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: white;
    box-shadow: var(--shadow-lg);
}

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

.news-item {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.news-date {
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.news-title {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.news-excerpt {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Education Timeline */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--gradient-primary);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    top: 0;
    width: 20px;
    height: 20px;
    background: var(--primary-color);
    border-radius: 50%;
    transform: translateX(-50%);
    border: 4px solid var(--bg-primary);
    box-shadow: var(--shadow-md);
}

.timeline-content {
    width: 45%;
    padding: 2rem;
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    position: relative;
}

.timeline-item:nth-child(odd) .timeline-content {
    left: 0;
}

.timeline-item:nth-child(even) .timeline-content {
    left: 55%;
}

.timeline-title {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.timeline-subtitle {
    color: var(--text-secondary);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.timeline-period {
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 1rem;
}

.timeline-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Publications */
.publication-filters {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--border-color);
    background: transparent;
    color: var(--text-secondary);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

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

.publications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.publication-item {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.publication-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.publication-type {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: var(--accent-color);
    color: white;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.publication-title {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.publication-authors {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.publication-venue {
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 1.5rem;
}

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

.link-btn {
    padding: 0.5rem 1rem;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    text-decoration: none;
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.link-btn:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

/* Projects */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.project-image {
    height: 200px;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: white;
}

.project-content {
    padding: 2rem;
}

.project-title {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.project-tags {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.tag {
    padding: 0.5rem 1rem;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
}

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

.project-link {
    padding: 0.75rem 1.5rem;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.project-link:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* Experience */
.experience-timeline {
    max-width: 800px;
    margin: 0 auto;
}

.experience-item {
    display: flex;
    gap: 2rem;
    margin-bottom: 3rem;
    align-items: flex-start;
}

.experience-period {
    min-width: 120px;
    padding: 0.5rem 1rem;
    background: var(--accent-color);
    color: white;
    border-radius: 20px;
    text-align: center;
    font-weight: 600;
    font-size: 0.9rem;
}

.experience-content {
    flex: 1;
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.experience-title {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.experience-organization {
    color: var(--text-secondary);
    font-weight: 600;
    margin-bottom: 1rem;
}

.experience-description {
    color: var(--text-secondary);
    line-height: 1.6;
    padding-left: 1.5rem;
}

.experience-description li {
    margin-bottom: 0.5rem;
}

/* Misc */
.misc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.misc-item {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.misc-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.misc-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 2rem;
    color: white;
}

.misc-title {
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.misc-list {
    list-style: none;
    color: var(--text-secondary);
    line-height: 1.6;
}

.misc-list li {
    margin-bottom: 0.5rem;
}

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 2rem;
}

.footer-title {
    margin-bottom: 1.5rem;
    color: var(--accent-color);
}

.contact-info p {
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.social-link {
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: var(--transition);
}

.social-link:hover {
    background: var(--accent-color);
    color: white;
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-light);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hamburger {
        display: flex;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .timeline-marker {
        left: 20px;
    }
    
    .timeline-content {
        width: calc(100% - 60px);
        left: 60px !important;
    }
    
    .experience-item {
        flex-direction: column;
        gap: 1rem;
    }
    
    .experience-period {
        min-width: auto;
        align-self: flex-start;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .section {
        padding: 4rem 0;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }
    
    .news-grid,
    .publications-grid,
    .projects-grid,
    .misc-grid {
        grid-template-columns: 1fr;
    }
}