/* ===== Base Reset & Variables ===== */
:root {
    --color-primary: #8b1a1a;
    --color-primary-light: #a82828;
    --color-primary-bg: #fdf6f6;
    --color-accent: #c0392b;
    --color-text: #2c3e50;
    --color-text-light: #636e72;
    --color-bg: #ffffff;
    --color-bg-alt: #f8f9fa;
    --color-border: #e8e8e8;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.1);
    --radius: 8px;
    --max-width: 960px;
    --transition: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 70px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.7;
    font-size: 15px;
}

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

a:hover {
    color: var(--color-primary-light);
}

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

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

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
}

.nav-logo {
    font-weight: 700;
    font-size: 18px;
    color: var(--color-primary);
}

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

.nav-menu a {
    color: var(--color-text-light);
    font-size: 14px;
    font-weight: 500;
    transition: color var(--transition);
    position: relative;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width var(--transition);
}

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

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

.lang-toggle {
    padding: 4px 14px;
    border: 1px solid var(--color-border);
    border-radius: 100px;
    background: transparent;
    color: var(--color-text);
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition);
    font-family: 'Inter', 'Noto Serif SC', sans-serif;
    white-space: nowrap;
    flex-shrink: 0;
}

.lang-toggle:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    width: 22px;
    height: 2px;
    background: var(--color-text);
    transition: var(--transition);
}

/* ===== Hero ===== */
.hero {
    padding: 120px 24px 60px;
    background: linear-gradient(135deg, var(--color-primary-bg) 0%, var(--color-bg) 100%);
}

.hero-container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 48px;
}

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

.photo-placeholder {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 60px;
    box-shadow: var(--shadow-lg);
}

.photo-placeholder img {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    object-fit: cover;
}

.hero-content h1 {
    font-size: 36px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 8px;
}

.name-cn {
    font-family: 'Noto Serif SC', serif;
    font-weight: 600;
    color: var(--color-text-light);
    font-size: 28px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--color-text-light);
    margin-bottom: 4px;
}

.hero-affiliation {
    font-size: 16px;
    margin-bottom: 4px;
}

.hero-workplace {
    font-size: 16px;
    margin-bottom: 4px;
}

.hero-graduation {
    font-size: 14px;
    color: var(--color-text-light);
    margin-bottom: 4px;
}

.job-market-tag {
    display: inline-block;
    padding: 1px 10px;
    background: var(--color-primary);
    color: white;
    font-size: 12px;
    font-weight: 600;
    border-radius: 100px;
    margin-left: 6px;
}

.hero-advisor {
    font-size: 14px;
    color: var(--color-text-light);
    margin-bottom: 4px;
}

.hero-advisor:last-of-type {
    margin-bottom: 20px;
}

.advisor-note {
    font-size: 12px;
    color: #999;
}

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

.hero-links a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 18px;
    border: 1px solid var(--color-border);
    border-radius: 100px;
    font-size: 13px;
    font-weight: 500;
    color: var(--color-text);
    transition: all var(--transition);
}

.hero-links a:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

/* ===== Sections ===== */
.section {
    padding: 72px 24px;
}

.section-alt {
    background: var(--color-bg-alt);
}

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

.section-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--color-text);
    position: relative;
    padding-bottom: 12px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 3px;
    background: var(--color-primary);
    border-radius: 2px;
}

.section-subtitle {
    color: var(--color-text-light);
    font-size: 14px;
    margin-bottom: 32px;
}

/* ===== Research Cards ===== */
.research-intro {
    font-size: 15px;
    line-height: 1.8;
    margin-bottom: 0;
    color: var(--color-text-light);
}

.research-intro strong {
    color: var(--color-text);
}

.research-areas {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.research-card {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 28px;
    transition: all var(--transition);
    position: relative;
}

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

.research-icon {
    width: 44px;
    height: 44px;
    border-radius: 10px;
    background: var(--color-primary-bg);
    color: var(--color-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    margin-bottom: 16px;
}

.research-card h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
}

.research-card p {
    font-size: 13px;
    color: var(--color-text-light);
    line-height: 1.7;
}

.research-tag {
    display: inline-block;
    margin-top: 12px;
    padding: 2px 10px;
    background: var(--color-primary-bg);
    color: var(--color-primary);
    font-size: 11px;
    font-weight: 600;
    border-radius: 100px;
}

/* ===== Publications ===== */
.publication-list {
    list-style: none;
    counter-reset: pub-counter;
}

.pub-item {
    counter-increment: pub-counter;
    padding: 20px 0 20px 0;
    border-bottom: 1px solid var(--color-border);
    position: relative;
}

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

.pub-title {
    display: block;
    font-weight: 600;
    font-size: 15px;
    line-height: 1.5;
    margin-bottom: 4px;
    color: var(--color-text);
}

.pub-authors {
    display: block;
    font-size: 13px;
    color: var(--color-text-light);
    margin-bottom: 2px;
}

.pub-authors u {
    color: var(--color-primary);
    font-weight: 500;
    text-decoration: none;
    border-bottom: 1px solid var(--color-primary);
}

.pub-venue {
    display: block;
    font-size: 13px;
    color: var(--color-text-light);
    font-style: italic;
}

.pub-badge {
    display: inline-block;
    margin-top: 6px;
    padding: 1px 8px;
    background: var(--color-primary);
    color: white;
    font-size: 10px;
    font-weight: 600;
    border-radius: 3px;
    letter-spacing: 0.3px;
}

.pub-links {
    display: inline-flex;
    gap: 8px;
    margin-top: 6px;
    margin-left: 8px;
}

.pub-links a {
    font-size: 12px;
    padding: 1px 8px;
    border: 1px solid var(--color-border);
    border-radius: 3px;
    color: var(--color-text-light);
}

.pub-links a:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
}

/* ===== Awards ===== */
.awards-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 32px;
}

.award-category h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-primary);
}

.award-category h3 i {
    margin-right: 6px;
    font-size: 14px;
}

.award-category ul {
    list-style: none;
}

.award-category li {
    font-size: 13px;
    padding: 6px 0;
    color: var(--color-text-light);
    border-bottom: 1px dashed var(--color-border);
    line-height: 1.5;
}

.award-category li:last-child {
    border-bottom: none;
}

/* ===== Timeline ===== */
.timeline {
    position: relative;
    padding-left: 28px;
    margin-top: 32px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 5px;
    top: 8px;
    bottom: 8px;
    width: 2px;
    background: var(--color-border);
}

.timeline-item {
    position: relative;
    padding-bottom: 28px;
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -25px;
    top: 6px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--color-primary);
    border: 2px solid white;
    box-shadow: 0 0 0 2px var(--color-primary);
}

.timeline-date {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 2px;
    font-variant-numeric: tabular-nums;
}

.timeline-content h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 2px;
}

.timeline-role {
    font-size: 13px;
    color: var(--color-text-light);
}

/* ===== Education ===== */
.education-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-top: 32px;
}

.edu-card {
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 28px;
    text-align: center;
    transition: all var(--transition);
}

.edu-card:hover {
    box-shadow: var(--shadow-md);
}

.edu-logo {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--color-primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 700;
    margin: 0 auto 16px;
}

.edu-card h3 {
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 4px;
}

.edu-degree {
    font-size: 14px;
    color: var(--color-text-light);
    margin-bottom: 4px;
}

.edu-date {
    font-size: 12px;
    color: #999;
}

/* ===== Footer ===== */
.footer {
    padding: 32px 24px;
    text-align: center;
    font-size: 13px;
    color: var(--color-text-light);
    border-top: 1px solid var(--color-border);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .hero-container {
        flex-direction: column;
        text-align: center;
    }

    .hero-links {
        justify-content: center;
    }

    .hero-content h1 {
        font-size: 28px;
    }

    .name-cn {
        font-size: 22px;
    }

    .photo-placeholder {
        width: 140px;
        height: 140px;
        font-size: 48px;
    }

    .research-areas {
        grid-template-columns: 1fr;
    }

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

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

    .nav-toggle {
        display: flex;
    }

    .lang-toggle {
        order: -1;
        margin-right: auto;
        margin-left: 12px;
    }

    .nav-menu {
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        gap: 0;
        padding: 8px 0;
        border-bottom: 1px solid var(--color-border);
        box-shadow: var(--shadow-md);
        display: none;
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-menu a {
        display: block;
        padding: 12px 24px;
    }

    .nav-menu a::after {
        display: none;
    }

    .section {
        padding: 48px 20px;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 100px 16px 40px;
    }

    .hero-content h1 {
        font-size: 24px;
    }
}