/* CSS Reset & Variables */
:root {
    --bg-color: #050505;
    --card-bg: #111111;
    --text-primary: #f0f0f0;
    --text-secondary: #888888;
    --accent: #ffffff;
    --border-color: #222222;
    --border-hover: #444444;
    --transition-speed: 0.3s;
    --max-width: 800px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3 {
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color var(--transition-speed) ease;
}

a:hover {
    color: var(--text-secondary);
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(5, 5, 5, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
}

.nav-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

.nav-links a {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

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

/* Main Layout */
main {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 6rem 2rem 4rem;
}

.section {
    margin-bottom: 5rem;
}

.section-title {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color);
}

/* Cards */
.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    transition: transform var(--transition-speed) ease, border-color var(--transition-speed) ease;
}

.card:hover {
    transform: translateY(-2px);
    border-color: var(--border-hover);
}

/* Hero Section */
.hero-section {
    padding: 4rem 0 6rem;
}

.hero-container {
    display: flex;
    align-items: center;
    gap: 3rem;
}

.hero-image img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--border-color);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    transition: transform var(--transition-speed) ease, border-color var(--transition-speed) ease;
}

.hero-image img:hover {
    transform: scale(1.05);
    border-color: var(--text-secondary);
}

.hero-title {
    font-size: 3rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #fff, #888);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    font-weight: 400;
    margin-bottom: 0.5rem;
}

.hero-affiliation {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.95rem;
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    transition: all var(--transition-speed) ease;
}

.contact-link:hover {
    border-color: var(--text-primary);
    color: var(--text-primary);
}

/* About Section */
#about .card p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}
#about .card p:last-child {
    margin-bottom: 0;
}
#about .card strong {
    color: var(--text-primary);
    font-weight: 500;
}

/* Timeline (Education & Experience) */
.timeline {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.timeline-item {
    padding: 1.5rem;
}

.timeline-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 0.25rem;
}

.timeline-header h3 {
    font-size: 1.1rem;
}

.timeline-date {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-family: 'Roboto Mono', monospace;
}

.timeline-institution {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-style: italic;
}

.timeline-details {
    list-style-type: none;
}

.timeline-details li {
    position: relative;
    padding-left: 1.2rem;
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.timeline-details li::before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--border-hover);
}

/* Publications */
.publication-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.publication-item {
    display: flex;
    gap: 1.5rem;
    padding: 1.5rem;
}

.pub-year {
    font-family: 'Roboto Mono', monospace;
    font-size: 0.9rem;
    color: var(--text-secondary);
    padding-top: 0.2rem;
}

.pub-details {
    flex: 1;
}

.pub-title {
    font-size: 1.05rem;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.pub-authors {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

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

.pub-venue {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    border-top: 1px solid var(--border-color);
    margin-top: 4rem;
}

.footer-content p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 600px) {
    .nav-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .hero-container {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
    }

    .hero-contact {
        justify-content: center;
        display: flex;
    }

    .timeline-header {
        flex-direction: column;
    }
    
    .timeline-date {
        margin-top: 0.25rem;
    }

    .publication-item {
        flex-direction: column;
        gap: 0.5rem;
    }
}