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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fafafa;
}

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

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    padding: 1rem 0;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

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

.nav-logo h2 {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 700;
}

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

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

.nav-link:hover {
    color: #667eea;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transition: width 0.3s ease;
}

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

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

.hamburger span {
    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;
    padding: 80px 0;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    opacity: 0.9;
}

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

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

.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 25px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-primary {
    background: white;
    color: #667eea;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #667eea;
    transform: translateY(-2px);
}

.profile-img {
    width: 400px;
    height: 400px;
    border-radius: 50%;
    object-fit: cover;
    border: 5px solid rgba(255, 255, 255, 0.2);
    animation: float 6s ease-in-out infinite;
}

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

/* Sections */
section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #333;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    width: 60px;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
}

/* About Section */
.about {
    background: white;
}

.about-text h3 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
    color: #667eea;
}

.about-text p {
    margin-bottom: 1rem;
    color: #666;
    line-height: 1.8;
}

.about-text ul {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

.about-text li {
    margin-bottom: 0.5rem;
    color: #666;
}

.contact-info p {
    margin-bottom: 0.5rem;
    color: #666;
}

.contact-info i {
    margin-right: 0.5rem;
    color: #667eea;
}

/* Research Section */
.research {
    background: #f8f9fa;
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.research-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    text-align: center;
}

.research-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
}

.research-card i {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.research-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #333;
}

.research-card p {
    color: #666;
    line-height: 1.6;
}

/* Publications Section */
.publications {
    background: white;
}

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

.publication-item h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #667eea;
}

.publication-item ul {
    list-style: none;
}

.publication-item li {
    padding: 1rem;
    margin-bottom: 1rem;
    background: #f8f9fa;
    border-radius: 10px;
    border-left: 4px solid #667eea;
    line-height: 1.6;
}

.publication-list {
    text-align: left;
}

.publication-section {
    margin-bottom: 2rem;
}

.publication-section h5 {
    color: #667eea;
    font-size: 1.2rem;
    margin-bottom: 1rem;
    border-bottom: 2px solid #667eea;
    padding-bottom: 0.5rem;
}

.publication-section ul {
    list-style: none;
    padding: 0;
}

.publication-section li {
    padding: 0.8rem;
    margin-bottom: 0.5rem;
    background: rgba(102, 126, 234, 0.05);
    border-left: 3px solid #764ba2;
    border-radius: 5px;
    font-size: 0.95rem;
    line-height: 1.5;
    transition: transform 0.2s ease;
}

.publication-section li:hover {
    transform: translateX(5px);
    background: rgba(102, 126, 234, 0.1);
}

.publication-section strong {
    color: #333;
}

.publication-section em {
    color: #667eea;
    font-style: normal;
}

/* Gallery Section */
.gallery {
    background: #f8f9fa;
}

.gallery-controls {
    text-align: center;
    margin-bottom: 2rem;
}

.gallery-btn {
    background: white;
    border: 2px solid #667eea;
    color: #667eea;
    padding: 8px 20px;
    margin: 0 5px;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.gallery-btn.active,
.gallery-btn:hover {
    background: #667eea;
    color: white;
}

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

.gallery-item {
    position: relative;
    overflow: hidden;
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.gallery-item:hover {
    transform: scale(1.05);
}

.gallery-item img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    display: block;
}

.gallery-item-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.gallery-item:hover .gallery-item-overlay {
    opacity: 1;
}

/* Upload Section */
.upload {
    background: white;
}

.upload-container {
    max-width: 600px;
    margin: 0 auto;
}

.upload-area {
    border: 3px dashed #667eea;
    border-radius: 15px;
    padding: 3rem;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: #764ba2;
    background: rgba(102, 126, 234, 0.05);
}

.upload-area i {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.upload-area h3 {
    margin-bottom: 1rem;
    color: #333;
}

.upload-area p {
    color: #666;
    margin-bottom: 1.5rem;
}

.upload-progress {
    margin: 2rem 0;
}

.progress-bar {
    width: 100%;
    height: 10px;
    background: #f0f0f0;
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transition: width 0.3s ease;
}

.uploaded-files {
    margin-top: 2rem;
}

.uploaded-files h3 {
    margin-bottom: 1rem;
    color: #333;
}

.files-list {
    display: grid;
    gap: 1rem;
}

.file-item {
    display: flex;
    align-items: center;
    padding: 1rem;
    background: #f8f9fa;
    border-radius: 10px;
    transition: transform 0.3s ease;
}

.file-item:hover {
    transform: translateX(5px);
}

.file-icon {
    font-size: 2rem;
    margin-right: 1rem;
    color: #667eea;
}

.file-info {
    flex: 1;
}

.file-name {
    font-weight: 600;
    color: #333;
}

.file-size {
    font-size: 0.9rem;
    color: #666;
}

.file-remove {
    background: #ff4757;
    color: white;
    border: none;
    padding: 5px 10px;
    border-radius: 15px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.file-remove:hover {
    background: #ff3742;
}

/* Lightbox Modal */
.lightbox-modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    animation: fadeIn 0.3s ease;
}

.lightbox-content {
    display: block;
    margin: auto;
    max-width: 90%;
    max-height: 90%;
    margin-top: 2%;
}

.close-lightbox {
    position: absolute;
    top: 20px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
}

.close-lightbox:hover {
    color: #bbb;
}

#lightboxCaption {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
    text-align: center;
    color: #ccc;
    padding: 10px 0;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Footer */
.footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

.social-links {
    margin-top: 1rem;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    margin: 0 10px;
    transition: color 0.3s ease;
}

.social-links a:hover {
    color: #667eea;
}

/* Responsive Design */
@media screen and (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-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .profile-img {
        width: 300px;
        height: 300px;
        margin: 0 auto;
    }
    
    .research-grid {
        grid-template-columns: 1fr;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
}

@media screen and (max-width: 480px) {
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 1rem;
    }
    
    .btn {
        width: 100%;
    }
}