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

:root {
    --primary: #2c5f7d;
    --primary-dark: #1e4459;
    --text: #2d3748;
    --text-light: #4a5568;
    --text-muted: #718096;
    --bg: #f7fafc;
    --card-bg: #ffffff;
    --border: #e2e8f0;
    --badge: #edf2f7;
    --badge-text: #4a5568;
    --accent: #d97706;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", sans-serif;
    color: var(--text);
    background: var(--bg);
    font-size: 12px;
    line-height: 1.5;
    overflow-x: hidden;
}

img {
    max-width: 100%;
}

a {
    color: inherit;
    text-decoration: none;
}

.page-wrapper {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: 240px;
    background: var(--card-bg);
    border-right: 1px solid var(--border);
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    scrollbar-width: none;
}

.sidebar::-webkit-scrollbar {
    display: none;
}

.sidebar-content {
    padding: 20px 16px;
}

.avatar {
    width: 100px;
    height: 100px;
    margin: 0 auto 12px;
    border-radius: 50%;
    overflow: hidden;
    border: 2px solid var(--border);
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.name {
    font-size: 1.15rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 2px;
    color: var(--text);
}

.title {
    font-size: 0.75rem;
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 10px;
}

.bio {
    text-align: center;
    padding: 10px 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    margin-bottom: 12px;
}

.bio p {
    font-size: 0.72rem;
    color: var(--text-light);
    margin-bottom: 2px;
}

.stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    margin-bottom: 14px;
}

.stat-item {
    text-align: center;
    padding: 8px;
    background: var(--bg);
    border-radius: 6px;
}

.stat-item strong {
    display: block;
    font-size: 0.85rem;
    color: var(--primary);
    margin-bottom: 2px;
}

.stat-item span {
    font-size: 0.65rem;
    color: var(--text-muted);
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 4px;
    margin-bottom: 14px;
}

.sidebar-nav a {
    padding: 6px 10px;
    border-radius: 4px;
    font-size: 0.75rem;
    color: var(--text-light);
    transition: all 0.2s;
}

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

.contact {
    margin-bottom: 12px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border);
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 0;
    font-size: 0.7rem;
    color: var(--text-light);
    transition: color 0.2s;
}

.contact-item:hover {
    color: var(--primary);
}

.contact-item .icon {
    font-size: 0.85rem;
}

.quick-links {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.btn-primary {
    display: block;
    text-align: center;
    padding: 6px 12px;
    background: var(--primary);
    color: white;
    border-radius: 4px;
    font-size: 0.72rem;
    font-weight: 600;
    transition: background 0.2s;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.main-content {
    margin-left: 240px;
    width: calc(100% - 240px);
    flex: none;
    padding: 24px 32px;
}

.section {
    margin-bottom: 28px;
    scroll-margin-top: 20px;
}

.section-title {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--text);
    padding-bottom: 6px;
    border-bottom: 2px solid var(--primary);
}

.project-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.project-card {
    display: block;
    padding: 12px;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 6px;
    transition: all 0.2s;
    cursor: pointer;
}

.project-card:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-color: var(--primary);
    transform: translateY(-2px);
}

.project-card h3 {
    font-size: 0.8rem;
    margin-bottom: 4px;
    color: var(--text);
    line-height: 1.4;
}

.project-meta {
    margin-bottom: 6px;
}

.badge {
    display: inline-block;
    padding: 2px 6px;
    background: var(--accent);
    color: white;
    border-radius: 3px;
    font-size: 0.6rem;
    font-weight: 600;
    line-height: 1.4;
}

.badge-muted {
    background: var(--badge);
    color: var(--badge-text);
}

.project-card p {
    font-size: 0.68rem;
    color: var(--text-light);
    line-height: 1.5;
    margin-bottom: 6px;
}

.project-card p strong {
    color: var(--text);
    font-weight: 600;
}

.project-links {
    display: flex;
    gap: 10px;
}

.link {
    font-size: 0.72rem;
    color: var(--primary);
    font-weight: 600;
    transition: color 0.2s;
}

.link:hover {
    color: var(--primary-dark);
    text-decoration: underline;
}

.achievement-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.achievement-list li {
    padding: 8px 12px;
    background: var(--card-bg);
    border-left: 2px solid var(--primary);
    border-radius: 3px;
    font-size: 0.75rem;
    color: var(--text-light);
}

.achievement-list li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 8px;
}

.achievement-list li a {
    color: inherit;
    transition: color 0.2s;
}

.achievement-list li a:hover {
    color: var(--primary);
}

.achievement-list strong {
    color: var(--accent);
    font-weight: 600;
}

.ach-date {
    font-size: 0.68rem;
    color: var(--text-muted);
    white-space: nowrap;
    flex-shrink: 0;
}

.research-content {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.research-item {
    padding: 10px;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 6px;
}

.research-item h3 {
    font-size: 0.82rem;
    margin-bottom: 3px;
    color: var(--text);
}

.research-item > p {
    font-size: 0.72rem;
    color: var(--text-light);
    margin-bottom: 8px;
}

.paper-item {
    margin-top: 8px;
    padding: 8px 10px;
    background: var(--bg);
    border-left: 2px solid var(--primary);
    border-radius: 3px;
}

.paper-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 8px;
    margin-bottom: 5px;
    flex-wrap: wrap;
}

.paper-title {
    font-size: 0.76rem;
    font-weight: 600;
    color: var(--text);
}

.paper-date {
    font-size: 0.68rem;
    color: var(--text-muted);
    white-space: nowrap;
}

.paper-desc {
    font-size: 0.7rem;
    color: var(--text-light);
    line-height: 1.55;
    margin-bottom: 4px;
}

.paper-contribution {
    font-size: 0.7rem;
    color: var(--text-light);
    line-height: 1.5;
    margin-bottom: 4px;
}

.paper-ref {
    font-size: 0.68rem;
    color: var(--text-muted);
    line-height: 1.5;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
}

.skill-category {
    padding: 10px;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 6px;
}

.skill-category h3 {
    font-size: 0.78rem;
    margin-bottom: 8px;
    color: var(--text);
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
}

.tags span {
    padding: 3px 6px;
    background: var(--bg);
    border-radius: 3px;
    font-size: 0.68rem;
    color: var(--text-muted);
}

.materials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
}

.material-card {
    padding: 10px;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 6px;
    transition: all 0.2s;
    display: block;
}

.material-card:hover {
    border-color: var(--primary);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

.material-card h3 {
    font-size: 0.8rem;
    margin-bottom: 3px;
    color: var(--text);
}

.material-card p {
    font-size: 0.7rem;
    color: var(--text-muted);
}

.footer {
    margin-top: 30px;
    padding-top: 14px;
    border-top: 1px solid var(--border);
    text-align: center;
}

.footer p {
    font-size: 0.7rem;
    color: var(--text-muted);
}

@media (max-width: 1024px) {
    .sidebar {
        position: static;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--border);
    }
    
    .main-content {
        margin-left: 0;
        width: 100%;
        padding: 20px 16px;
    }
    
    .page-wrapper {
        flex-direction: column;
    }
    
    .skills-grid,
    .materials-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    body {
        font-size: 11px;
    }

    .sidebar-content {
        padding: 16px 12px;
    }

    .avatar {
        width: 84px;
        height: 84px;
        margin-bottom: 10px;
    }

    .name {
        font-size: 1.05rem;
    }

    .title,
    .bio p,
    .contact-item,
    .btn-primary,
    .footer p {
        font-size: 0.78rem;
    }

    .stats {
        gap: 6px;
    }

    .stat-item {
        padding: 7px 6px;
    }

    .stat-item strong {
        font-size: 0.8rem;
    }

    .stat-item span {
        font-size: 0.7rem;
    }

    .sidebar-nav {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 6px;
    }

    .sidebar-nav a {
        padding: 7px 8px;
        text-align: center;
        font-size: 0.76rem;
    }

    .contact {
        display: flex;
        flex-direction: column;
        gap: 2px;
    }

    .main-content {
        padding: 16px 12px 24px;
    }

    .section {
        margin-bottom: 20px;
    }

    .section-title {
        font-size: 0.95rem;
        margin-bottom: 10px;
    }

    .achievement-list li,
    .research-item p,
    .material-card p,
    .tags span {
        font-size: 0.74rem;
    }

    .research-item,
    .material-card,
    .skill-category,
    .project-card,
    .achievement-list li {
        padding: 9px;
    }

    .research-item h3,
    .material-card h3,
    .skill-category h3,
    .project-card h3 {
        font-size: 0.82rem;
    }

    .project-card p {
        font-size: 0.74rem;
        line-height: 1.6;
    }

    .badge {
        font-size: 0.68rem;
    }

    .project-links {
        flex-wrap: wrap;
    }
}