:root {
    --primary: #2c3e50;
    --accent: #3498db;
    --bg: #fafafa;
    --card-bg: #fff;
    --text: #333;
    --text-light: #666;
    --border: #e0e0e0;
}

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

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    line-height: 1.7;
    color: var(--text);
    background-color: var(--bg);
}

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

a:hover {
    text-decoration: underline;
}

/* Header */
header {
    background: var(--primary);
    color: #fff;
    padding: 3rem 1rem;
    text-align: center;
}

header h1 {
    font-size: 2.4rem;
    font-weight: 700;
    margin-bottom: 0.3rem;
}

header .subtitle {
    font-size: 1.15rem;
    font-weight: 300;
    opacity: 0.9;
    margin-bottom: 1rem;
}

header .contact-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
    font-size: 0.9rem;
}

header .contact-links a {
    color: rgba(255,255,255,0.85);
}

header .contact-links a:hover {
    color: #fff;
}

/* Nav */
nav {
    background: #34495e;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
    max-width: 900px;
    margin: 0 auto;
}

nav ul li a {
    display: block;
    color: rgba(255,255,255,0.8);
    padding: 0.75rem 1.2rem;
    font-size: 0.9rem;
    font-weight: 600;
    transition: color 0.2s, background 0.2s;
}

nav ul li a:hover,
nav ul li a:focus {
    color: #fff;
    background: rgba(255,255,255,0.1);
    text-decoration: none;
}

/* Main */
main {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

section {
    background: var(--card-bg);
    margin-bottom: 1.5rem;
    padding: 2rem;
    border-radius: 6px;
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

section h2 {
    color: var(--primary);
    font-size: 1.5rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--accent);
}

/* About */
#about .research-interests {
    margin-top: 1rem;
}

#about .research-interests span {
    display: inline-block;
    background: #eaf2f8;
    color: var(--primary);
    padding: 0.25rem 0.7rem;
    border-radius: 3px;
    font-size: 0.85rem;
    margin: 0.2rem;
}

/* Metrics bar */
.metrics {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.metrics .metric {
    text-align: center;
}

.metrics .metric .number {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--accent);
}

.metrics .metric .label {
    font-size: 0.8rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Timeline entries (education) */
.timeline-entry {
    position: relative;
    padding-left: 1.2rem;
    margin-bottom: 1.5rem;
    border-left: 3px solid var(--accent);
}

.timeline-entry:last-child {
    margin-bottom: 0;
}

.timeline-entry .period {
    font-size: 0.85rem;
    color: var(--text-light);
    font-weight: 600;
}

.timeline-entry .role {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--primary);
}

.timeline-entry .org {
    font-size: 0.95rem;
    color: var(--text);
}

.timeline-entry .location {
    font-size: 0.85rem;
    color: var(--text-light);
}

.timeline-entry .description {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-top: 0.3rem;
}

/* Experience entries with logos */
.exp-entry {
    display: flex;
    gap: 1rem;
    padding: 1.2rem 0;
    border-bottom: 1px solid var(--border);
}

.exp-entry:first-of-type {
    padding-top: 0;
}

.exp-entry:last-of-type {
    border-bottom: none;
    padding-bottom: 0;
}

.exp-logo {
    width: 52px;
    height: 52px;
    border-radius: 6px;
    flex-shrink: 0;
    object-fit: contain;
}

.exp-content {
    flex: 1;
    min-width: 0;
}

.exp-content .role {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1.3;
}

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

.exp-content .period {
    font-size: 0.85rem;
    color: var(--text-light);
}

.exp-content .location {
    font-size: 0.85rem;
    color: var(--text-light);
}

.exp-content .description {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-top: 0.4rem;
    line-height: 1.5;
}

/* Publications */
.publication {
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border);
}

.publication:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.publication .pub-title {
    font-weight: 700;
    font-size: 1rem;
    color: var(--primary);
}

.publication .pub-authors {
    font-size: 0.9rem;
    color: var(--text-light);
    margin: 0.2rem 0;
}

.publication .pub-venue {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent);
}

.publication .pub-links {
    margin-top: 0.3rem;
}

.publication .pub-links a {
    display: inline-block;
    font-size: 0.8rem;
    padding: 0.15rem 0.6rem;
    border: 1px solid var(--accent);
    border-radius: 3px;
    margin-right: 0.4rem;
    transition: background 0.2s, color 0.2s;
}

.publication .pub-links a:hover {
    background: var(--accent);
    color: #fff;
    text-decoration: none;
}

/* Skills */
.skills-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.skills-grid .skill-group h3 {
    font-size: 0.95rem;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.skills-grid .skill-group ul {
    list-style: none;
}

.skills-grid .skill-group li {
    font-size: 0.9rem;
    padding: 0.15rem 0;
    color: var(--text-light);
}

/* Reviewer */
.reviewer-list {
    columns: 2;
    column-gap: 2rem;
}

.reviewer-list .year-entry {
    break-inside: avoid;
    margin-bottom: 0.8rem;
}

.reviewer-list .year-entry strong {
    color: var(--primary);
}

.reviewer-list .year-entry span {
    font-size: 0.9rem;
    color: var(--text-light);
}

/* Footer */
footer {
    background: var(--primary);
    color: rgba(255,255,255,0.7);
    text-align: center;
    padding: 1.5rem 1rem;
    font-size: 0.85rem;
}

footer .social-links {
    margin-bottom: 0.5rem;
}

footer .social-links a {
    color: rgba(255,255,255,0.8);
    margin: 0 0.8rem;
    font-weight: 600;
}

footer .social-links a:hover {
    color: #fff;
}

/* Responsive */
@media screen and (max-width: 600px) {
    header h1 {
        font-size: 1.8rem;
    }

    nav ul {
        flex-wrap: wrap;
    }

    nav ul li a {
        padding: 0.5rem 0.8rem;
        font-size: 0.8rem;
    }

    main {
        padding: 1rem 0.5rem;
    }

    section {
        padding: 1.2rem;
    }

    .skills-grid {
        grid-template-columns: 1fr;
    }

    .reviewer-list {
        columns: 1;
    }

    .metrics {
        gap: 1rem;
    }
}