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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #ffffff;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all 0.3s ease;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo a {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2563eb;
    text-decoration: none;
    transition: color 0.3s ease;
}

.nav-logo a:hover {
    color: #1d4ed8;
}

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

.nav-link {
    color: #333;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: #2563eb;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #2563eb;
    transition: width 0.3s ease;
}

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

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

.bar {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.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 1000 1000"><defs><radialGradient id="a" cx="50%" cy="50%"><stop offset="0%" stop-color="%23ffffff" stop-opacity="0.1"/><stop offset="100%" stop-color="%23ffffff" stop-opacity="0"/></radialGradient></defs><circle cx="200" cy="200" r="100" fill="url(%23a)"/><circle cx="800" cy="300" r="150" fill="url(%23a)"/><circle cx="400" cy="700" r="120" fill="url(%23a)"/></svg>');
    opacity: 0.1;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 800px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.highlight {
    color: #fbbf24;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: 1.5rem;
    opacity: 0.9;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.8;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.btn {
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    border: 2px solid transparent;
}

.btn-primary {
    background: #fbbf24;
    color: #1f2937;
}

.btn-primary:hover {
    background: #f59e0b;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(251, 191, 36, 0.3);
}

.btn-secondary {
    background: transparent;
    color: white;
    border-color: white;
}

.btn-secondary:hover {
    background: white;
    color: #1f2937;
    transform: translateY(-2px);
}

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

.social-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: #2563eb;
    border-radius: 50%;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.social-link:hover {
    background: #fbbf24;
    color: #1f2937;
    transform: translateY(-3px);
}

/* Section Styles */
section {
    padding: 80px 0;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: #1f2937;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, #2563eb, #7c3aed);
    border-radius: 2px;
}

/* About Section */
.about {
    background: #f8fafc;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-text p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
    color: #4b5563;
    line-height: 1.7;
}

.about-stats {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-top: 3rem;
}

.stat {
    text-align: center;
}

.stat h3 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #2563eb;
    margin-bottom: 0.5rem;
}

.stat p {
    color: #6b7280;
    font-weight: 500;
}

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

.timeline::before {
    content: '';
    position: absolute;
    left: 30px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: #e5e7eb;
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    padding-left: 80px;
}

.timeline-marker {
    position: absolute;
    left: 20px;
    top: 0;
    width: 20px;
    height: 20px;
    background: #2563eb;
    border-radius: 50%;
    border: 4px solid white;
    box-shadow: 0 0 0 4px #e5e7eb;
}

.timeline-content {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border: 1px solid #e5e7eb;
}

.timeline-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.timeline-content h4 {
    font-size: 1.1rem;
    color: #2563eb;
    margin-bottom: 0.5rem;
}

.timeline-date {
    color: #6b7280;
    font-size: 0.9rem;
    font-weight: 500;
}

.timeline-location {
    color: #6b7280;
    font-size: 0.9rem;
    margin-left: 1rem;
}

.timeline-content p {
    margin-top: 1rem;
    color: #4b5563;
    line-height: 1.6;
}

.experience-list {
    margin-top: 1rem;
    padding-left: 1.5rem;
}

.experience-list li {
    margin-bottom: 0.8rem;
    color: #4b5563;
    line-height: 1.6;
}

/* Education Section */
.education {
    background: #f8fafc;
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.education-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border: 1px solid #e5e7eb;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.education-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.education-header {
    margin-bottom: 1rem;
}

.education-header h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.education-location {
    color: #6b7280;
    font-size: 0.9rem;
}

.education-details h4 {
    font-size: 1.1rem;
    color: #2563eb;
    margin-bottom: 0.5rem;
}

.education-gpa {
    font-size: 1rem;
    font-weight: 600;
    color: #059669;
    margin-bottom: 0.5rem;
}

.education-date {
    color: #6b7280;
    font-size: 0.9rem;
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.skill-category {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border: 1px solid #e5e7eb;
    transition: transform 0.3s ease;
}

.skill-category:hover {
    transform: translateY(-3px);
}

.skill-category h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1.5rem;
    text-align: center;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
    justify-content: center;
}

.skill-tag {
    background: linear-gradient(135deg, #2563eb, #7c3aed);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: transform 0.3s ease;
}

.skill-tag:hover {
    transform: scale(1.05);
}

/* Publications Section */
.publications {
    background: #f8fafc;
}

.publications-list {
    max-width: 800px;
    margin: 0 auto;
}

.publication-item {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border: 1px solid #e5e7eb;
    margin-bottom: 2rem;
    transition: transform 0.3s ease;
}

.publication-item:hover {
    transform: translateY(-3px);
}

.publication-item h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.8rem;
    line-height: 1.4;
}

.publication-authors {
    color: #2563eb;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.publication-journal {
    color: #6b7280;
    font-style: italic;
}

/* Contact Section */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact-info h3 {
    font-size: 2rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

.contact-info p {
    font-size: 1.1rem;
    color: #4b5563;
    margin-bottom: 2rem;
    line-height: 1.6;
}

.contact-details {
    margin-bottom: 2rem;
}

.contact-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
    font-size: 1.1rem;
    color: #4b5563;
}

.contact-item i {
    color: #2563eb;
    font-size: 1.2rem;
    width: 20px;
}

.contact-link {
    color: #2563eb;
    text-decoration: none;
    transition: color 0.3s ease;
}

.contact-link:hover {
    color: #1d4ed8;
    text-decoration: underline;
}

.contact-social {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

.footer p {
    color: #9ca3af;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .about-stats {
        flex-direction: column;
        gap: 2rem;
    }
    
    .education-grid {
        grid-template-columns: 1fr;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .timeline::before {
        left: 15px;
    }
    
    .timeline-item {
        padding-left: 50px;
    }
    
    .timeline-marker {
        left: 5px;
    }
    
    .timeline-content {
        padding: 1.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .timeline-content {
        padding: 1rem;
    }
    
    .education-card {
        padding: 1.5rem;
    }
    
    .skill-category {
        padding: 1.5rem;
    }
    
    .publication-item {
        padding: 1.5rem;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.timeline-item {
    animation: fadeInUp 0.6s ease-out;
}

.education-card {
    animation: fadeInUp 0.6s ease-out;
}

.skill-category {
    animation: fadeInUp 0.6s ease-out;
}

.publication-item {
    animation: fadeInUp 0.6s ease-out;
}

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

/* Custom scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #2563eb;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #1d4ed8;
}