/* Global Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: hidden;
}

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

/* Navigation Bar */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    transition: var(--transition);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

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

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

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

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

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

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

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--white);
    padding: 80px 20px 40px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: grid-move 20s linear infinite;
}

@keyframes grid-move {
    0% { transform: translate(0, 0); }
    100% { transform: translate(50px, 50px); }
}

.hero-content {
    text-align: center;
    z-index: 1;
    animation: fade-in-up 1s ease;
}

@keyframes fade-in-up {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.highlight {
    background: linear-gradient(120deg, #ffd89b 0%, #19547b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

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

.btn {
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    display: inline-block;
}

.btn-primary {
    background: var(--white);
    color: var(--primary-color);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

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

.btn-secondary:hover {
    background: var(--white);
    color: var(--primary-color);
    transform: translateY(-3px);
}

.social-links {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
}

.social-links a {
    color: var(--white);
    font-size: 1.5rem;
    transition: var(--transition);
}

.social-links a:hover {
    transform: translateY(-5px);
    opacity: 0.8;
}

.hero-animation {
    position: absolute;
    right: 10%;
    top: 50%;
    transform: translateY(-50%);
    opacity: 0.2;
}

.code-block {
    background: rgba(255, 255, 255, 0.1);
    padding: 20px;
    border-radius: 10px;
    font-family: 'Courier New', monospace;
    font-size: 1.2rem;
}

.code-line {
    margin: 10px 0;
}

.keyword {
    color: #ffd89b;
}

.function {
    color: #a8e6cf;
}

.string {
    color: #ffaaa5;
}

/* About Section */
.about {
    padding: 80px 20px;
    background: var(--light-bg);
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-dark);
    position: relative;
    display: inline-block;
    width: 100%;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: var(--gradient);
    border-radius: 2px;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-text {
    font-size: 1.1rem;
    color: var(--text-light);
}

.about-text p {
    margin-bottom: 1rem;
}

.skills-list {
    list-style: none;
    margin-top: 1.5rem;
}

.skills-list li {
    margin: 0.8rem 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skills-list i {
    color: var(--primary-color);
}

.skills-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.skill-card {
    background: var(--white);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.skill-card:hover {
    transform: translateY(-5px);
}

.skill-card i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.skill-card h3 {
    margin-bottom: 0.5rem;
}

.skill-bar {
    background: #e2e8f0;
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background: var(--gradient);
    border-radius: 4px;
    transition: width 1s ease;
}

/* Publications Section */
.publications {
    padding: 80px 20px;
    background: var(--white);
}

/* Publications Carousel */
.publications-carousel {
    position: relative;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 60px;
}

.publications-carousel-wrapper {
    overflow: hidden;
    width: 100%;
}

.publications-carousel-track {
    display: flex;
    transition: transform 0.5s ease-in-out;
    gap: 2rem;
}

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

.publication-card {
    background: var(--white);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    flex: 0 0 calc(33.333% - 1.35rem);
    min-width: 0;
    max-width: calc(33.333% - 1.35rem);
}

/* Carousel Navigation Buttons */
.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: var(--white);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    font-size: 1.2rem;
    color: var(--primary-color);
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    transition: all 0.3s ease;
    z-index: 10;
}

.carousel-btn:hover {
    background: var(--primary-color);
    color: var(--white);
    transform: translateY(-50%) scale(1.1);
}

.carousel-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.carousel-btn:disabled:hover {
    background: var(--white);
    color: var(--primary-color);
    transform: translateY(-50%);
}

.carousel-btn-prev {
    left: 0;
}

.carousel-btn-next {
    right: 0;
}

/* Carousel Indicators */
.carousel-indicators {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 2rem;
}

.carousel-indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #ddd;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
}

.carousel-indicator.active {
    background: var(--primary-color);
    width: 30px;
    border-radius: 6px;
}

.carousel-indicator:hover {
    background: var(--secondary-color);
}

.publication-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
}

.publication-image {
    background: var(--gradient);
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
}

.publication-image i {
    font-size: 4rem;
}

.publication-content {
    padding: 1.5rem;
    overflow: hidden;
}

.publication-content h3 {
    margin-bottom: 0.8rem;
    color: var(--text-dark);
    font-size: 1.2rem;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.publication-content .authors {
    color: var(--text-dark);
    font-weight: 400;
    margin-bottom: 0.3rem;
    font-size: 0.95rem;
}

.publication-content .authors strong {
    font-weight: 700;
    color: var(--primary-color);
}

.publication-content .journal {
    color: var(--text-light);
    margin-bottom: 0.8rem;
    font-size: 0.9rem;
}

.publication-content .abstract {
    color: var(--text-light);
    margin-bottom: 1rem;
    line-height: 1.6;
    font-size: 0.95rem;
}

.publication-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tag {
    background: #e0e7ff;
    color: var(--primary-color);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
}

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

.publication-link {
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.3rem;
    transition: var(--transition);
}

.publication-link:hover {
    color: var(--secondary-color);
}

.publication-link.disabled {
    color: var(--text-light);
    cursor: not-allowed;
}

/* Teaching Section */
.teaching {
    padding: 80px 20px;
    background: var(--white);
}

.teaching-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.teaching-item {
    background: var(--light-bg);
    border-radius: 15px;
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    display: flex;
    gap: 1.5rem;
}

.teaching-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
}

.teaching-icon {
    font-size: 3rem;
    color: var(--primary-color);
    min-width: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.teaching-content h3 {
    color: var(--text-dark);
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.teaching-institution,
.teaching-location,
.teaching-date {
    color: var(--text-light);
    margin: 0.5rem 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.teaching-institution i,
.teaching-location i,
.teaching-date i {
    color: var(--primary-color);
    width: 20px;
}

/* Academic Service Section */
.service {
    padding: 80px 20px;
    background: var(--light-bg);
}

.service-content {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.service-category {
    background: var(--white);
    border-radius: 15px;
    padding: 2rem;
    box-shadow: var(--shadow);
}

.service-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.service-header i {
    font-size: 2rem;
    color: var(--primary-color);
}

.service-header h3 {
    color: var(--text-dark);
    font-size: 1.5rem;
    margin: 0;
}

.service-items {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.service-badge {
    background: var(--gradient);
    color: var(--white);
    padding: 0.5rem 1.5rem;
    border-radius: 25px;
    font-weight: 600;
    font-size: 0.95rem;
    box-shadow: 0 4px 10px rgba(102, 126, 234, 0.3);
    transition: var(--transition);
}

.service-badge:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 15px rgba(102, 126, 234, 0.4);
}

/* Honors & Awards Section */
.honors {
    padding: 80px 20px;
    background: var(--white);
}

.honors-timeline {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.honor-item {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
    position: relative;
}

.honor-item::before {
    content: '';
    position: absolute;
    left: 85px;
    top: 50px;
    width: 2px;
    height: calc(100% + 2rem);
    background: linear-gradient(180deg, var(--primary-color) 0%, transparent 100%);
}

.honor-item:last-child::before {
    display: none;
}

.honor-year {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    min-width: 80px;
    text-align: center;
    background: var(--light-bg);
    padding: 0.5rem 1rem;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.honor-content {
    flex: 1;
    display: flex;
    gap: 1.5rem;
    background: var(--light-bg);
    padding: 1.5rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.honor-content:hover {
    transform: translateX(10px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.honor-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

.honor-details h3 {
    color: var(--text-dark);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.honor-institution {
    color: var(--text-light);
    font-size: 1rem;
}

/* Contact Section */
.contact {
    padding: 80px 20px;
    background: var(--light-bg);
}

.contact-content {
    max-width: 1200px;
    margin: 0 auto;
}

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

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: var(--white);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.contact-item i {
    font-size: 2rem;
    color: var(--primary-color);
}

.contact-item h4 {
    margin-bottom: 0.3rem;
}

.contact-item p {
    color: var(--text-light);
}

.contact-item a:hover {
    color: var(--primary-color) !important;
    transition: var(--transition);
}

/* Visitor Map Section */
.visitor-map-section {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
    margin-top: 2rem;
}

.map-title {
    font-size: 1.8rem;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.map-title i {
    color: var(--primary-color);
}

.map-description {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    font-size: 1rem;
}

.visitor-stats {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    justify-content: center;
    flex-wrap: wrap;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 1rem 2rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
    min-width: 150px;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--white);
    line-height: 1;
}

.stat-label {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.9);
    margin-top: 0.5rem;
}

.visitor-map {
    width: 100%;
    height: 500px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 2px solid #e2e8f0;
}

/* Leaflet popup customization */
.leaflet-popup-content-wrapper {
    border-radius: 10px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
}

.leaflet-popup-content {
    margin: 15px;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.popup-content h4 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.popup-content p {
    margin: 0.3rem 0;
    color: var(--text-dark);
}

/* Footer */
.footer {
    background: var(--dark-bg);
    color: var(--white);
    padding: 2rem 20px;
    text-align: center;
}

.footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-links a {
    color: var(--white);
    font-size: 1.5rem;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--primary-color);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: var(--white);
        width: 100%;
        text-align: center;
        transition: var(--transition);
        box-shadow: var(--shadow);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hamburger {
        display: flex;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .hero-animation {
        display: none;
    }

    .about-content {
        grid-template-columns: 1fr;
    }
    
    .contact-info {
        grid-template-columns: 1fr;
    }

    .skills-grid {
        grid-template-columns: 1fr;
    }

    .publications-grid {
        grid-template-columns: 1fr;
    }
    
    .publications-carousel {
        padding: 0 50px;
    }
    
    .publication-card {
        flex: 0 0 100%;
        max-width: 100%;
    }
    
    .carousel-btn {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }
    
    .teaching-grid {
        grid-template-columns: 1fr;
    }
    
    .teaching-item {
        flex-direction: column;
        text-align: center;
    }
    
    .teaching-icon {
        margin: 0 auto;
    }
    
    .honor-item {
        flex-direction: column;
        gap: 1rem;
    }
    
    .honor-item::before {
        display: none;
    }
    
    .honor-year {
        align-self: flex-start;
    }
    
    .honor-content {
        flex-direction: column;
        text-align: center;
    }

    .footer .container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .visitor-map {
        height: 350px;
    }
    
    .visitor-stats {
        gap: 1rem;
    }
    
    .stat-item {
        min-width: 120px;
        padding: 0.8rem 1.5rem;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .map-title {
        font-size: 1.5rem;
    }
}

/* Citation Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: var(--white);
    margin: 10% auto;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    width: 90%;
    max-width: 700px;
    position: relative;
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        transform: translateY(-50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-content h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.close {
    color: var(--text-light);
    position: absolute;
    right: 1.5rem;
    top: 1.5rem;
    font-size: 2rem;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
}

.close:hover,
.close:focus {
    color: var(--primary-color);
}

#citationText {
    background: var(--light-bg);
    padding: 1.5rem;
    border-radius: 8px;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
    color: var(--text-dark);
    border: 1px solid #e2e8f0;
    max-height: 400px;
    overflow-y: auto;
}

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

.skill-card {
    animation: float 3s ease-in-out infinite;
}

.skill-card:nth-child(2) {
    animation-delay: 0.5s;
}

.skill-card:nth-child(3) {
    animation-delay: 1s;
}

.skill-card:nth-child(4) {
    animation-delay: 1.5s;
}