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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #f0f0f0;
    background-color: #1a1a1a;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Light Theme */
body.light-theme {
    color: #333;
    background-color: #f9f9f9;
}

body.light-theme nav {
    background-color: #2c3e50;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

body.light-theme .hero {
    background: white;
    color: #333;
}

body.light-theme .profile-img {
    border: 3px solid #ddd;
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
    background-color: #ddd;
}

body.light-theme section {
    background-color: white;
}

body.light-theme section h3 {
    color: #2c3e50;
}

body.light-theme .subsection-heading {
    color: #34495e !important;
}

body.light-theme .publication-item {
    background-color: #f8f9fa;
}

body.light-theme .publication-item h4 {
    color: #2c3e50;
}

body.light-theme .publication-item .authors {
    color: #555;
}

body.light-theme .publication-item .venue {
    color: #7f8c8d;
}

body.light-theme .publication-item .links a,
body.light-theme .contact a {
    color: #3498db;
}

body.light-theme .social-links a {
    background-color: #3498db;
    color: white;
}

body.light-theme .social-links a:hover {
    background-color: #2980b9;
}

body.light-theme .research-interests li {
    background-color: #ecf0f1;
}

body.light-theme details summary {
    color: #2980b9 !important;
}

body.light-theme details p {
    color: #333 !important;
    border-left-color: #3498db !important;
}

body.light-theme footer {
    background-color: #2c3e50;
    color: white;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Theme Toggle Button */
.theme-toggle {
    background: none;
    border: 2px solid white;
    color: white;
    padding: 0.4rem 0.8rem;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    font-weight: 500;
}

.theme-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

body.light-theme .theme-toggle {
    border-color: white;
    color: white;
}

/* Navigation */
nav {
    background-color: #0f0f0f;
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 5px rgba(0,0,0,0.5);
    transition: background-color 0.3s ease;
}

.nav-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.logo {
    font-size: 1.5rem;
    font-weight: 600;
}

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

.nav-links a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
    font-weight: 500;
}

.nav-links a:hover,
.nav-links a.active {
    color: #3498db;
}

/* Hero Section */
.hero {
    background: #1f1f1f;
    color: #f5f5f5;
    padding: 4rem 0;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.profile {
    display: flex;
    align-items: flex-start;
    gap: 2rem;
}

.profile-img {
    width: 320px;
    height: 400px;
    border-radius: 10px;
    object-fit: cover;
    object-position: 40% center;
    border: 3px solid #333;
    box-shadow: 0 4px 10px rgba(0,0,0,0.5);
    background-color: #333;
    flex-shrink: 0;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.profile-info h2 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.position {
    font-size: 1.3rem;
    margin-bottom: 0.3rem;
    opacity: 0.95;
}

.affiliation {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Sections */
section {
    padding: 3rem 0;
    background-color: #1f1f1f;
    margin-bottom: 2rem;
    transition: background-color 0.3s ease;
}

.contact {
    padding-top: 1rem;
}

section h3 {
    font-size: 2rem;
    color: #ffffff;
    margin-bottom: 1.5rem;
    border-bottom: 3px solid #3498db;
    padding-bottom: 0.5rem;
    transition: color 0.3s ease;
}

section p {
    margin-bottom: 1rem;
    font-size: 1.1rem;
    line-height: 1.8;
}

/* Research Interests */
.research-interests ul {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
}

.research-interests li {
    background-color: #2a2a2a;
    padding: 1rem;
    border-left: 4px solid #3498db;
    font-size: 1.05rem;
    transition: background-color 0.3s ease;
}

/* Contact Section */
.contact p {
    margin-bottom: 0.8rem;
}

.contact a {
    color: #5dade2;
    text-decoration: none;
    transition: color 0.3s ease;
}

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

.social-links {
    display: flex;
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.social-links a {
    background-color: #3498db;
    color: white;
    padding: 0.6rem 1.2rem;
    border-radius: 5px;
    text-decoration: none;
    transition: background-color 0.3s;
}

.social-links a:hover {
    background-color: #2980b9;
}

/* Publications */
.publication-item {
    margin-bottom: 2rem;
    padding: 1.5rem;
    background-color: #2a2a2a;
    border-left: 4px solid #3498db;
    transition: background-color 0.3s ease;
}

.publication-item h4 {
    font-size: 1.2rem;
    color: #ffffff;
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

.publication-item .authors {
    font-style: italic;
    margin-bottom: 0.3rem;
    color: #c0c0c0;
    transition: color 0.3s ease;
}

.publication-item .venue {
    color: #a0a0a0;
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

.publication-item .links a {
    color: #5dade2;
    margin-right: 1rem;
    text-decoration: none;
    transition: color 0.3s ease;
}

.publication-item .links a:hover {
    text-decoration: underline;
}

/* Footer */
footer {
    background-color: #0f0f0f;
    color: #c0c0c0;
    padding: 2rem 0;
    text-align: center;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-links {
        gap: 1rem;
    }
    
    .profile {
        flex-direction: column;
        text-align: center;
    }
    
    .profile-info h2 {
        font-size: 2rem;
    }
    
    .social-links {
        flex-direction: column;
    }
}