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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell,
        "Open Sans", "Helvetica Neue", sans-serif;
    line-height: 1.6;
    color: #2c3e50;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    width: 90%;
    max-width: 1000px;
    margin: 0 auto;
    padding: 1rem;
}

/* Header */
.site-header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
}

.logo h1 {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.site-nav a {
    text-decoration: none;
    color: #2c3e50;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    transition: all 0.3s ease;
    position: relative;
}

.site-nav a:hover {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

/* Sections */
.section {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    margin: 2rem 0;
    border-radius: 20px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.section:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
}

.section.alternate {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.98) 0%, rgba(248, 250, 252, 0.95) 100%);
    border: 1px solid rgba(102, 126, 234, 0.1);
}

.section h2 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 2rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: center;
}

/* Hero section */
.hero-section {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(255, 255, 255, 0.95) 100%);
    backdrop-filter: blur(15px);
    margin: 2rem 0;
    border-radius: 25px;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
    overflow: hidden;
}

.hero-content {
    display: flex;
    align-items: center;
    gap: 3rem;
    padding: 3rem 1rem;
}

.hero-image {
    flex-shrink: 0;
    position: relative;
}

.hero-image img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: 0 8px 32px rgba(102, 126, 234, 0.3);
    border: 4px solid rgba(255, 255, 255, 0.5);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.hero-image img:hover {
    transform: scale(1.05);
    box-shadow: 0 12px 40px rgba(102, 126, 234, 0.4);
}

.hero-text h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: left;
}

.hero-text p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: #555;
    line-height: 1.8;
}

/* Button styles */
.btn {
    display: inline-block;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-decoration: none;
    padding: 1rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.6);
    color: white;
}

/* Publications and Projects */
.publication-item,
.project-item {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    padding: 2rem;
    margin-bottom: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
    background-image: linear-gradient(white, white), linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    background-origin: border-box;
    background-clip: padding-box, border-box;
}

.publication-item:hover,
.project-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.publication-item h3,
.project-item h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.authors {
    font-style: italic;
    color: #666;
    margin-bottom: 0.3rem;
}

.journal {
    font-weight: 600;
    color: #667eea;
    margin-bottom: 1rem;
}

.description {
    color: #555;
    line-height: 1.7;
}

/* Contact section */
#contact {
    text-align: center;
}

#contact p {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: #555;
}

#contact a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
}

#contact a:hover {
    color: #764ba2;
}

/* Footer */
.site-footer {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    color: #fff;
    padding: 2rem 0;
    margin-top: 3rem;
    text-align: center;
}

.site-footer p {
    font-size: 0.9rem;
    opacity: 0.9;
}

/* Abstract toggle functionality */
.abstract-toggle {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.85rem;
    margin-left: 0.5rem;
    transition: all 0.3s ease;
    box-shadow: 0 3px 10px rgba(102, 126, 234, 0.3);
}

.abstract-toggle:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.abstract-content {
    margin-top: 1.5rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border: 1px solid rgba(102, 126, 234, 0.2);
    border-radius: 12px;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.abstract-content p {
    font-size: 0.95rem;
    line-height: 1.7;
    color: #555;
}

.paper-link {
    display: inline-block;
    background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    font-size: 0.85rem;
    margin-left: 0.5rem;
    transition: all 0.3s ease;
    box-shadow: 0 3px 10px rgba(52, 152, 219, 0.3);
}

.paper-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.4);
    color: white;
}

/* Responsive design */
@media (max-width: 768px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
        gap: 2rem;
    }
    
    .hero-image img {
        width: 150px;
        height: 150px;
    }
    
    .hero-text h2 {
        font-size: 2rem;
        text-align: center;
    }
    
    .site-nav ul {
        gap: 1rem;
    }
    
    .site-nav a {
        padding: 0.4rem 0.8rem;
        font-size: 0.9rem;
    }
}