/* ===== CSS Variables ===== */
:root {
    --primary-color: #2c3e50;
    --accent-color: #3498db;
    --accent-hover: #2980b9;
    --text-color: #333;
    --text-light: #666;
    --text-muted: #888;
    --bg-color: #fff;
    --bg-light: #f8f9fa;
    --bg-section: #fafbfc;
    --border-color: #e9ecef;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.1);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
    --max-width: 1000px;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-serif: 'Crimson Pro', Georgia, serif;
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--bg-color);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--accent-hover);
}

img {
    max-width: 100%;
    height: auto;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.navbar.scrolled {
    border-bottom-color: var(--border-color);
    box-shadow: var(--shadow-sm);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 64px;
}

.nav-logo {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-menu a {
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 8px 0;
    position: relative;
}

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

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

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

/* ===== Hero Section ===== */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(180deg, var(--bg-light) 0%, var(--bg-color) 100%);
}

.hero-content {
    display: flex;
    gap: 60px;
    align-items: flex-start;
}

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

.hero-image img {
    width: 220px;
    height: 220px;
    border-radius: var(--radius-lg);
    object-fit: cover;
    box-shadow: var(--shadow-md);
}

.hero-text h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.hero-text .title {
    font-size: 1.1rem;
    color: var(--accent-color);
    font-weight: 500;
    margin-bottom: 4px;
}

.hero-text .affiliation {
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.hero-text .bio {
    font-size: 0.95rem;
    color: var(--text-light);
    margin-bottom: 16px;
    line-height: 1.8;
}

.hero-text .bio strong {
    color: var(--text-color);
}

.social-links {
    display: flex;
    gap: 16px;
    margin-top: 24px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    background: var(--bg-light);
    color: var(--text-light);
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--accent-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

/* ===== Section Styles ===== */
.section-title {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 8px;
    letter-spacing: -0.3px;
}

.section-subtitle {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 32px;
}

/* ===== News Section ===== */
.news {
    padding: 80px 0;
    background: var(--bg-color);
}

.news-list {
    margin-top: 24px;
}

.news-item {
    display: flex;
    gap: 24px;
    padding: 16px 0;
    border-bottom: 1px solid var(--border-color);
}

.news-item:last-child {
    border-bottom: none;
}

.news-date {
    flex-shrink: 0;
    width: 80px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--accent-color);
}

.news-content {
    font-size: 0.95rem;
    color: var(--text-light);
}

.news-content strong {
    color: var(--primary-color);
    font-weight: 600;
}

/* ===== Publications Section ===== */
.publications {
    padding: 80px 0;
    background: var(--bg-section);
}

.pub-list {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.pub-item {
    display: flex;
    gap: 28px;
    padding: 24px;
    background: var(--bg-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.pub-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.pub-teaser {
    flex-shrink: 0;
    width: 240px;
}

.pub-teaser img {
    width: 100%;
    height: 150px;
    object-fit: cover;
    border-radius: var(--radius-sm);
    background: var(--bg-light);
}

.pub-info {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.pub-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--primary-color);
    line-height: 1.5;
    margin-bottom: 10px;
}

.pub-authors {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 8px;
}

.pub-authors strong {
    color: var(--text-color);
}

.pub-venue {
    font-size: 0.9rem;
    margin-bottom: 14px;
}

.venue-name {
    font-weight: 600;
    color: var(--accent-color);
}

.venue-note {
    color: var(--text-muted);
    font-size: 0.85rem;
}

.pub-links {
    display: flex;
    gap: 12px;
    margin-top: auto;
}

.pub-link {
    display: inline-block;
    padding: 6px 14px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--accent-color);
    background: rgba(52, 152, 219, 0.1);
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.pub-link:hover {
    background: var(--accent-color);
    color: white;
}

/* ===== Contact Section ===== */
.contact {
    padding: 80px 0;
    background: var(--bg-color);
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-top: 24px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    color: var(--text-light);
}

.contact-item svg {
    flex-shrink: 0;
    color: var(--accent-color);
    margin-top: 2px;
}

/* ===== Easter Egg Section ===== */
.easter-egg {
    padding: 60px 0;
    background: linear-gradient(180deg, var(--bg-section) 0%, var(--bg-light) 100%);
}

.easter-egg-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    cursor: pointer;
    padding: 16px 32px;
    background: var(--bg-color);
    border-radius: 50px;
    box-shadow: var(--shadow-sm);
    max-width: 280px;
    margin: 0 auto;
    transition: var(--transition);
}

.easter-egg-toggle:hover {
    box-shadow: var(--shadow-md);
    transform: scale(1.02);
}

.heart {
    font-size: 1.2rem;
    animation: heartbeat 1.5s ease-in-out infinite;
}

@keyframes heartbeat {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.toggle-text {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-light);
}

.easter-egg-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease, opacity 0.3s ease;
    opacity: 0;
}

.easter-egg-content.show {
    max-height: 800px;
    opacity: 1;
    margin-top: 40px;
}

.partner-section {
    background: var(--bg-color);
    border-radius: var(--radius-lg);
    padding: 40px;
    box-shadow: var(--shadow-md);
}

.partner-header {
    text-align: center;
    margin-bottom: 32px;
}

.partner-header h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 8px;
}

.partner-subtitle {
    color: var(--text-muted);
    font-style: italic;
}

.partner-profile {
    display: flex;
    gap: 32px;
    align-items: flex-start;
    margin-bottom: 32px;
}

.partner-image img {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: var(--shadow-sm);
}

.partner-info h4 {
    font-size: 1.25rem;
    color: var(--primary-color);
    margin-bottom: 4px;
}

.partner-title {
    color: var(--accent-color);
    font-weight: 500;
    font-size: 0.95rem;
    margin-bottom: 4px;
}

.partner-affiliation {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 12px;
}

.partner-bio {
    color: var(--text-light);
    font-size: 0.9rem;
    line-height: 1.7;
    margin-bottom: 12px;
}

.partner-links {
    display: flex;
    gap: 16px;
}

.partner-links a {
    font-size: 0.85rem;
    font-weight: 500;
}

.partner-publications h4 {
    font-size: 1rem;
    color: var(--primary-color);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-color);
}

.partner-pub-item {
    display: flex;
    gap: 16px;
    padding: 10px 0;
}

.partner-pub-venue {
    flex-shrink: 0;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent-color);
    width: 100px;
}

.partner-pub-title {
    font-size: 0.9rem;
    color: var(--text-light);
}

.love-note {
    text-align: center;
    margin-top: 24px;
    font-style: italic;
    color: var(--text-muted);
}

/* ===== Footer ===== */
.footer {
    padding: 40px 0;
    background: var(--primary-color);
    color: rgba(255,255,255,0.7);
    text-align: center;
}

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

.footer-note {
    font-size: 0.8rem;
    margin-top: 8px;
    opacity: 0.6;
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .nav-menu {
        gap: 20px;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 32px;
    }
    
    .hero-image img {
        width: 180px;
        height: 180px;
    }
    
    .hero-text h1 {
        font-size: 2rem;
    }
    
    .social-links {
        justify-content: center;
    }
    
    .pub-item {
        flex-direction: column;
    }
    
    .pub-teaser {
        width: 100%;
    }
    
    .pub-teaser img {
        height: 180px;
    }
    
    .partner-profile {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .partner-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .nav-container {
        height: 56px;
    }
    
    .nav-logo {
        font-size: 1.1rem;
    }
    
    .nav-menu {
        gap: 12px;
    }
    
    .nav-menu a {
        font-size: 0.8rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .news-item {
        flex-direction: column;
        gap: 4px;
    }
    
    .news-date {
        width: auto;
    }
    
    .pub-item {
        padding: 16px;
    }
    
    .partner-section {
        padding: 24px;
    }
}