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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

header {
    background: linear-gradient(135deg, #2c3e50, #34495e);
    color: white;
    padding: 3rem 0;
    text-align: center;
}

header h1 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
}

.subtitle {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    opacity: 0.9;
}

.contact-info p {
    margin: 0.5rem 0;
    display: inline-block;
    margin-right: 2rem;
}

.contact-info i {
    margin-right: 0.5rem;
}

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

.social-links a {
    color: white;
    font-size: 1.5rem;
    margin: 0 1rem;
    transition: color 0.3s;
}

.social-links a:hover {
    color: #3498db;
}

nav {
    background: #2c3e50;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
    padding: 1rem 0;
}

nav li {
    margin: 0 1rem;
}

nav a {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background 0.3s;
}

nav a:hover {
    background: #34495e;
}

section {
    padding: 4rem 0;
    border-bottom: 1px solid #eaeaea;
}

section:last-of-type {
    border-bottom: none;
}

h2 {
    font-size: 2.5rem;
    margin-bottom: 2rem;
    color: #2c3e50;
    text-align: center;
}

.timeline-item {
    background: white;
    padding: 2rem;
    margin-bottom: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-left: 4px solid #3498db;
}

.timeline-item h3 {
    color: #2c3e50;
    margin-bottom: 0.5rem;
}

.date {
    color: #7f8c8d;
    font-style: italic;
    margin-bottom: 1rem;
}

.achievement {
    background: #e8f4f8;
    padding: 0.5rem;
    border-radius: 4px;
    margin-top: 1rem;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

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

.project-card h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

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

.conference {
    color: #e74c3c;
    font-weight: bold;
    margin: 0.5rem 0;
}

.authors {
    color: #7f8c8d;
    font-style: italic;
}

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

.skill-category {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    text-align: center;
}

.skill-category h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    
    nav li {
        margin: 0.5rem 0;
    }
    
    .contact-info p {
        display: block;
        margin-right: 0;
    }
}