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

html {
    scroll-behavior: smooth;
}

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

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

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

h1 {
    font-size: 3rem;
    font-weight: 700;
}

h2 {
    font-size: 2.5rem;
}

h3 {
    font-size: 1.8rem;
}

h4 {
    font-size: 1.4rem;
}

p {
    margin-bottom: 1rem;
    color: #666;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 8px;
    font-weight: 500;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    font-size: 1rem;
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: transparent;
    color: #667eea;
    border: 2px solid #667eea;
}

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

.btn-outline {
    background: transparent;
    color: #333;
    border: 2px solid #ddd;
    padding: 10px 20px;
    margin: 5px;
}

.btn-outline:hover {
    background: #f8f9fa;
    border-color: #667eea;
    color: #667eea;
}

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

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: 0 2px 20px 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;
}

.nav-logo h2 {
    color: #333;
    font-size: 1.5rem;
    margin: 0;
}

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

.nav-link {
    color: #333;
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
    transition: color 0.3s ease;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: #667eea;
    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, #f5f7fa 0%, #c3cfe2 100%);
    padding-top: 80px;
}

.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;
    color: #333;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: #666;
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.hero-description {
    font-size: 1.1rem;
    color: #777;
    margin-bottom: 2rem;
    line-height: 1.7;
}

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

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

.profile-placeholder {
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 20px 40px rgba(102, 126, 234, 0.3);
}

.profile-placeholder i {
    font-size: 8rem;
    color: white;
}

/* Section Styles */
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;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 2px;
}

/* About Section */
.about {
    background: #f8f9fa;
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-text h3 {
    color: #333;
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.about-text h3:first-child {
    margin-top: 0;
}

.education-item {
    background: white;
    padding: 1.5rem;
    margin-bottom: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.education-item h4 {
    color: #667eea;
    margin-bottom: 0.5rem;
}

.memberships-list {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.memberships-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #eee;
    position: relative;
    padding-left: 1.5rem;
}

.memberships-list li:last-child {
    border-bottom: none;
}

.memberships-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #667eea;
    font-weight: bold;
}

.awards {
    display: grid;
    gap: 1rem;
    margin-top: 1rem;
}

.award-item {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border-left: 4px solid #667eea;
}

.award-item h4 {
    color: #667eea;
    margin-bottom: 0.5rem;
}

/* Career Progression Styles */
.career-progression {
    margin-top: 1rem;
}

.career-item {
    margin-bottom: 1.5rem;
    padding: 1rem;
    background: white;
    border-radius: 8px;
    border-left: 4px solid #667eea;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.career-item h4 {
    color: #667eea;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.career-item p {
    color: #666;
    font-size: 0.95rem;
    margin: 0;
}

/* Research Section */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.research-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.research-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.research-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.research-icon i {
    font-size: 2rem;
    color: white;
}

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

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

/* Publications Section */
.publications {
    background: #f8f9fa;
}

.publications-intro {
    text-align: center;
    font-size: 1.1rem;
    max-width: 800px;
    margin: 0 auto 3rem;
    color: #666;
}

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

.category {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.category h3 {
    color: #667eea;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #eee;
}

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

.publication-list li {
    padding: 0.8rem 0;
    border-bottom: 1px solid #f0f0f0;
    position: relative;
    padding-left: 1.5rem;
    color: #666;
}

.publication-list li:last-child {
    border-bottom: none;
}

.publication-list li::before {
    content: '📄';
    position: absolute;
    left: 0;
}

.publication-links {
    text-align: center;
}

/* Teaching Section */
.teaching-overview {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 3rem;
}

.teaching-overview h3 {
    color: #333;
    margin-bottom: 1rem;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin: 3rem 0;
}

.course-card {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 3px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.course-card:hover {
    transform: translateY(-3px);
}

.course-card h4 {
    color: #667eea;
    margin-bottom: 1rem;
}

.academic-service {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 12px;
    margin-top: 3rem;
}

.academic-service h3 {
    color: #333;
    margin-bottom: 1.5rem;
}

.academic-service ul {
    list-style: none;
}

.academic-service li {
    padding: 0.5rem 0;
    position: relative;
    padding-left: 1.5rem;
    color: #666;
}

.academic-service li::before {
    content: '▶';
    position: absolute;
    left: 0;
    color: #667eea;
}

/* Contact Section */
.contact {
    background: #f8f9fa;
}

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

.contact-info {
    display: grid;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 3px 15px rgba(0, 0, 0, 0.1);
}

.contact-icon {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-icon i {
    color: white;
    font-size: 1.2rem;
}

.contact-details h3 {
    color: #333;
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.contact-details p {
    color: #666;
    margin: 0;
}

.contact-details a {
    color: #667eea;
}

.contact-details a:hover {
    text-decoration: underline;
}

.contact-form {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.contact-form h3 {
    color: #333;
    margin-bottom: 1.5rem;
    text-align: center;
}

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

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #eee;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* Footer */
.footer {
    background: #333;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-info h3 {
    color: white;
    margin-bottom: 1rem;
}

.footer-info p {
    color: #ccc;
}

.footer-links h4 {
    color: white;
    margin-bottom: 1rem;
}

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

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

.footer-links a {
    color: #ccc;
    transition: color 0.3s ease;
}

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

.footer-social h4 {
    color: white;
    margin-bottom: 1rem;
}

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

.social-links a {
    width: 40px;
    height: 40px;
    background: #555;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: #667eea;
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #555;
    color: #ccc;
}

/* 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;
    }
    
    .nav-menu li {
        margin: 1rem 0;
    }
    
    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }
    
    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }
    
    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .profile-placeholder {
        width: 200px;
        height: 200px;
    }
    
    .profile-placeholder i {
        font-size: 5rem;
    }
    
    .research-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .social-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 250px;
    }
    
    .research-card,
    .course-card {
        padding: 1.5rem;
    }
    
    .contact-form {
        padding: 1.5rem;
    }
}

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

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

/* Scroll animations will be handled by JavaScript */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease-out;
}

.animate-on-scroll.animated {
    opacity: 1;
    transform: translateY(0);
}

/* Loading states */
.loading {
    opacity: 0.7;
    pointer-events: none;
}

/* Focus styles for accessibility */
.btn:focus,
input:focus,
textarea:focus,
.nav-link:focus {
    outline: 2px solid #667eea;
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .navbar,
    .hamburger,
    .hero-buttons,
    .contact-form,
    .footer {
        display: none;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.4;
    }
    
    .hero {
        min-height: auto;
        padding: 1rem 0;
    }
    
    section {
        padding: 1rem 0;
        page-break-inside: avoid;
    }
}