/* 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(20px);
    z-index: 1000;
    padding: 1rem 0;
    transition: all 0.3s ease;
}

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

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

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

.nav-link {
    text-decoration: none;
    color: #64748b;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: #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-color: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    z-index: 1;
}

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

.hero-content {
    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;
    line-height: 1.2;
}

.gradient-text {
    background: linear-gradient(90deg, #667eea 0%, #fbbf24 50%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    color: transparent;
    transition: none;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    line-height: 1.6;
}

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

.btn {
    padding: 12px 24px;
    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: #667eea;
    transform: translateY(-2px);
}

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

.social-link {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-3px);
}

.profile-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.profile-img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 1rem;
    border: 4px solid rgba(255, 255, 255, 0.3);
}

.profile-info h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.profile-info p {
    opacity: 0.8;
    margin-bottom: 0.25rem;
}

/* Section Headers */
.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 1rem;
}

.section-header p {
    font-size: 1.1rem;
    color: #64748b;
    max-width: 600px;
    margin: 0 auto;
}

/* Scroll offset for fixed navbar */
section {
    scroll-margin-top: 120px;
    position: relative;
    z-index: 2;
}

/* Additional padding adjustment for better positioning */
section:not(.hero) {
    padding-top: 120px !important;
}

/* About Section */
.about {
    padding: 100px 0 80px 0;
    background: #f8fafc;
}

.about-content {
    display: grid;
    gap: 4rem;
    margin-top: 1rem;
}

.about-text {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.about-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border-left: 4px solid #2563eb;
}

.about-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

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

.skill-category {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

.skill-category h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skill-category h4 i {
    color: #2563eb;
}

.skill-category ul {
    list-style: none;
}

.skill-category li {
    padding: 0.5rem 0;
    color: #64748b;
    position: relative;
    padding-left: 1.5rem;
}

.skill-category li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: #2563eb;
}

/* Research Section */
.research {
    padding: 100px 0 80px 0;
}

.research-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-bottom: 4rem;
    margin-top: 1rem;
}

.stat-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2rem;
    border-radius: 15px;
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
}

.publications-list {
    margin-bottom: 4rem;
}

.publication-item {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    margin-bottom: 2rem;
    border-left: 4px solid #2563eb;
}

.pub-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.pub-header h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: #1f2937;
    flex: 1;
}

.pub-year {
    background: #e0e7ff;
    color: #3730a3;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.pub-authors {
    color: #64748b;
    margin-bottom: 0.5rem;
}

.pub-journal {
    color: #475569;
    font-style: italic;
    margin-bottom: 1rem;
}

.pub-actions {
    display: flex;
    gap: 1rem;
}

.pub-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border: 1px solid #2563eb;
    border-radius: 20px;
    transition: all 0.3s ease;
}

.pub-link:hover {
    background: #2563eb;
    color: white;
}

.research-interests {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 15px;
}

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

.interests-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
}

.interest-tag {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    font-weight: 500;
    font-size: 0.9rem;
}

/* Projects Section */
.projects {
    padding: 100px 0 80px 0;
    background: #f8fafc;
}

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

.project-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.project-image {
    height: 200px;
    overflow: hidden;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.project-card:hover .project-image img {
    transform: scale(1.05);
}

.project-content {
    padding: 2rem;
}

.project-content h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

.project-content p {
    color: #64748b;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

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

.tech-tag {
    background: #e0e7ff;
    color: #3730a3;
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 500;
}

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

.project-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.3s ease;
}

.project-link:hover {
    color: #1d4ed8;
}

/* Blog Section */
.blog {
    padding: 100px 0 80px 0;
}

.blog-grid {
    display: grid;
    gap: 2rem;
    margin-bottom: 3rem;
}

.blog-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.blog-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.blog-card.featured {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0;
}

.blog-image {
    height: 250px;
    overflow: hidden;
    position: relative;
}

.blog-card.featured .blog-image {
    height: auto;
}

.blog-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.blog-card:hover .blog-image img {
    transform: scale(1.05);
}

.blog-category {
    position: absolute;
    top: 1rem;
    left: 1rem;
    background: #fbbf24;
    color: #1f2937;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.blog-content {
    padding: 2rem;
}

.blog-meta {
    display: flex;
    justify-content: space-between;
    margin-bottom: 1rem;
    color: #64748b;
    font-size: 0.9rem;
}

.blog-content h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
    line-height: 1.4;
}

.blog-content p {
    color: #64748b;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.read-more {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.3s ease;
}

.read-more:hover {
    color: #1d4ed8;
}

.read-more i {
    font-size: 0.8rem;
    transition: transform 0.3s ease;
}

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

.blog-cta {
    text-align: center;
}

/* Contact Section */
/* Hide link style for see email */
#show-email {
    color: inherit;
    text-decoration: none;
    cursor: pointer;
    font-weight: normal;
}
#show-email:hover {
    text-decoration: underline dotted;
    color: inherit;
}
.contact {
    padding: 100px 0 80px 0;
    background: #f8fafc;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    text-align: center;
}

.contact-card i {
    font-size: 2rem;
    color: #2563eb;
    margin-bottom: 1rem;
}

.contact-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.contact-card p {
    color: #64748b;
}

.contact-form {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e2e8f0;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #2563eb;
}

.form-group textarea {
    resize: vertical;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    font-weight: 600;
}

.footer-section p {
    opacity: 0.8;
    line-height: 1.6;
    margin-bottom: 1rem;
}

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

.footer-social a {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: background-color 0.3s ease;
}

.footer-social a:hover {
    background: rgba(255, 255, 255, 0.2);
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 2rem;
    text-align: center;
    opacity: 0.8;
}

/* 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-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .about-text {
        grid-template-columns: 1fr;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .research-stats {
        grid-template-columns: 1fr;
    }
    
    .pub-header {
        flex-direction: column;
        gap: 1rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .blog-card.featured {
        grid-template-columns: 1fr;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-header h2 {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 1rem;
        align-items: stretch;
    }
    .hero-buttons a, .hero-buttons button {
        font-size: 1.1rem;
        font-weight: 600;
        padding: 0.9rem 0.5rem;
        min-width: 140px;
        margin: 0 auto;
        box-shadow: 0 2px 8px rgba(99,102,241,0.12);
        letter-spacing: 0.01em;
    }
    .read-more {
        font-size: 1.05rem;
        font-weight: 600;
        padding: 0.8rem 0.5rem;
        min-width: 120px;
        margin: 0.5rem auto;
        letter-spacing: 0.01em;
    }
}

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

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-4 {
    margin-bottom: 2rem;
}

.mt-4 {
    margin-top: 2rem;
}

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

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

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

::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}