/* ============================================
   个人网页 - 主样式文件
   使用 CSS3 现代特性：Grid, Flexbox, 动画, 变量
   ============================================ */

/* --- CSS 变量 --- */
:root {
    --primary: #4f46e5;
    --primary-light: #818cf8;
    --primary-dark: #3730a3;
    --accent: #06b6d4;
    --bg: #f8fafc;
    --bg-card: #ffffff;
    --text: #1e293b;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 4px 24px rgba(0,0,0,0.06);
    --shadow-hover: 0 12px 40px rgba(0,0,0,0.12);
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

/* --- 重置 & 基础 --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    min-height: 100vh;
}

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

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

/* --- 导航栏 --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
}

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary);
}

.nav-logo .logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
}

.nav-links {
    display: flex;
    gap: 6px;
    list-style: none;
}

.nav-links a {
    padding: 8px 18px;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
    background: rgba(79, 70, 229, 0.08);
}

/* 移动端菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.menu-toggle span {
    width: 24px;
    height: 2.5px;
    background: var(--text);
    border-radius: 2px;
    transition: var(--transition);
}

/* --- 主内容区 --- */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 92px 24px 60px;
}

/* --- 页面板块通用 --- */
.section {
    display: none;
    animation: fadeIn 0.5s ease;
}

.section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to   { opacity: 1; transform: translateY(0); }
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-header h2 {
    font-size: 2.2rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 12px;
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   主页板块
   ============================================ */
.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    min-height: calc(100vh - 160px);
    padding: 40px 0;
}

.hero-text h1 {
    font-size: 3.2rem;
    font-weight: 900;
    line-height: 1.15;
    margin-bottom: 20px;
}

.hero-text h1 .gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--accent), #10b981);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-text .subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
    line-height: 1.8;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: var(--transition);
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
    box-shadow: 0 4px 16px rgba(79, 70, 229, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(79, 70, 229, 0.4);
    color: white;
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

/* 头像区域 */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.avatar-wrapper {
    position: relative;
    width: 320px;
    height: 320px;
}

.avatar-circle {
    width: 280px;
    height: 280px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 6rem;
    color: white;
    box-shadow: 0 20px 60px rgba(79, 70, 229, 0.3);
    position: relative;
    z-index: 2;
    margin: 20px;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

.avatar-ring {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border: 3px dashed var(--primary-light);
    border-radius: 50%;
    animation: spin 20s linear infinite;
    opacity: 0.4;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to   { transform: rotate(360deg); }
}

/* 技能卡片 */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 24px;
    margin-top: 48px;
}

.skill-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px 24px;
    text-align: center;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.skill-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transform: scaleX(0);
    transition: var(--transition);
}

.skill-card:hover::before {
    transform: scaleX(1);
}

.skill-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.skill-icon {
    width: 60px;
    height: 60px;
    border-radius: 16px;
    background: linear-gradient(135deg, rgba(79,70,229,0.1), rgba(6,182,212,0.1));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    margin: 0 auto 20px;
}

.skill-card h3 {
    font-size: 1.15rem;
    margin-bottom: 8px;
}

.skill-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* 统计条 */
.stats-bar {
    display: flex;
    gap: 40px;
    justify-content: center;
    margin-top: 48px;
    padding: 32px;
    background: var(--bg-card);
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 900;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 4px;
}

/* ============================================
   文件管理板块
   ============================================ */
.file-toolbar {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: 24px;
}

.search-box {
    flex: 1;
    min-width: 200px;
    position: relative;
}

.search-box input {
    width: 100%;
    padding: 12px 16px 12px 44px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    background: var(--bg-card);
    transition: var(--transition);
    font-family: var(--font);
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79,70,229,0.1);
}

.search-box .search-icon {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.1rem;
}

.btn-icon {
    padding: 12px 20px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: var(--bg-card);
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
    font-family: var(--font);
}

.btn-icon:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: rgba(79,70,229,0.04);
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 20px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    flex-wrap: wrap;
}

.breadcrumb a {
    color: var(--primary);
}

.breadcrumb .sep {
    color: var(--border);
}

/* 文件网格 */
.file-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 16px;
}

.file-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 20px 16px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.file-item:hover {
    border-color: var(--primary-light);
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.file-item.selected {
    border-color: var(--primary);
    background: rgba(79,70,229,0.04);
}

.file-icon {
    font-size: 2.8rem;
    margin-bottom: 12px;
    display: block;
}

.file-name {
    font-size: 0.85rem;
    font-weight: 500;
    word-break: break-all;
    line-height: 1.4;
    margin-bottom: 6px;
}

.file-meta {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.file-checkbox {
    position: absolute;
    top: 8px;
    left: 8px;
    width: 18px;
    height: 18px;
    accent-color: var(--primary);
}

/* 文件列表视图 */
.file-list {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.file-list-header {
    display: grid;
    grid-template-columns: 40px 1fr 100px 120px 100px;
    padding: 14px 20px;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.file-list-row {
    display: grid;
    grid-template-columns: 40px 1fr 100px 120px 100px;
    padding: 14px 20px;
    align-items: center;
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
    cursor: pointer;
}

.file-list-row:last-child {
    border-bottom: none;
}

.file-list-row:hover {
    background: rgba(79,70,229,0.03);
}

.file-list-row .fname {
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 10px;
}

/* 上传区域 */
.upload-zone {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 48px 24px;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
    margin-bottom: 24px;
    background: var(--bg-card);
}

.upload-zone:hover,
.upload-zone.dragover {
    border-color: var(--primary);
    background: rgba(79,70,229,0.03);
}

.upload-zone .upload-icon {
    font-size: 3rem;
    margin-bottom: 12px;
    display: block;
}

.upload-zone p {
    color: var(--text-secondary);
}

/* 视图切换 */
.view-toggle {
    display: flex;
    gap: 4px;
    background: var(--bg);
    border-radius: 8px;
    padding: 4px;
    border: 1px solid var(--border);
}

.view-toggle button {
    padding: 8px 12px;
    border: none;
    background: transparent;
    border-radius: 6px;
    cursor: pointer;
    font-size: 1.1rem;
    transition: var(--transition);
    font-family: var(--font);
}

.view-toggle button.active {
    background: white;
    box-shadow: 0 1px 4px rgba(0,0,0,0.1);
}

/* ============================================
   视频教程板块
   ============================================ */
.video-filters {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 32px;
    justify-content: center;
}

.filter-btn {
    padding: 10px 22px;
    border-radius: 30px;
    border: 1px solid var(--border);
    background: var(--bg-card);
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
    font-family: var(--font);
}

.filter-btn.active,
.filter-btn:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 28px;
}

.video-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: var(--transition);
}

.video-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.video-thumb {
    position: relative;
    width: 100%;
    aspect-ratio: 16/9;
    background: linear-gradient(135deg, #1e293b, #334155);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    overflow: hidden;
}

.video-thumb .play-btn {
    width: 60px;
    height: 60px;
    background: rgba(255,255,255,0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--primary);
    transition: var(--transition);
    z-index: 2;
}

.video-thumb:hover .play-btn {
    transform: scale(1.1);
    background: white;
}

.video-thumb .duration {
    position: absolute;
    bottom: 10px;
    right: 10px;
    background: rgba(0,0,0,0.75);
    color: white;
    padding: 3px 8px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 600;
}

.video-info {
    padding: 20px;
}

.video-info h3 {
    font-size: 1.05rem;
    margin-bottom: 8px;
    line-height: 1.5;
}

.video-info .video-desc {
    color: var(--text-secondary);
    font-size: 0.88rem;
    margin-bottom: 14px;
    line-height: 1.6;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.82rem;
    color: var(--text-secondary);
}

.video-meta .tags {
    display: flex;
    gap: 6px;
}

.tag {
    padding: 3px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 500;
}

.tag-blue { background: rgba(79,70,229,0.1); color: var(--primary); }
.tag-green { background: rgba(16,185,129,0.1); color: var(--success); }
.tag-orange { background: rgba(245,158,11,0.1); color: var(--warning); }
.tag-purple { background: rgba(139,92,246,0.1); color: #8b5cf6; }

/* 视频播放器模态框 */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.7);
    backdrop-filter: blur(8px);
    z-index: 2000;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.modal-overlay.active {
    display: flex;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius);
    max-width: 900px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalIn 0.3s ease;
}

@keyframes modalIn {
    from { opacity: 0; transform: scale(0.9); }
    to   { opacity: 1; transform: scale(1); }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
}

.modal-header h3 {
    font-size: 1.2rem;
}

.modal-close {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: none;
    background: var(--bg);
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.modal-close:hover {
    background: var(--danger);
    color: white;
}

.modal-body {
    padding: 24px;
}

.video-player {
    width: 100%;
    aspect-ratio: 16/9;
    background: #000;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    margin-bottom: 20px;
}

/* ============================================
   免责声明板块
   ============================================ */
.disclaimer-container {
    max-width: 800px;
    margin: 0 auto;
}

.disclaimer-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 40px;
    margin-bottom: 24px;
}

.disclaimer-card h3 {
    font-size: 1.3rem;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.disclaimer-card p,
.disclaimer-card li {
    color: var(--text-secondary);
    line-height: 1.9;
    margin-bottom: 10px;
}

.disclaimer-card ul {
    padding-left: 20px;
    margin-bottom: 10px;
}

.disclaimer-card li {
    margin-bottom: 6px;
}

.disclaimer-warning {
    background: linear-gradient(135deg, rgba(245,158,11,0.08), rgba(245,158,11,0.02));
    border: 1px solid rgba(245,158,11,0.3);
    border-radius: var(--radius-sm);
    padding: 20px;
    margin: 20px 0;
    display: flex;
    gap: 14px;
    align-items: flex-start;
}

.disclaimer-warning .warn-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.disclaimer-update {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 20px;
}

/* ============================================
   关于我 板块
   ============================================ */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: start;
}

.about-text h2 {
    font-size: 2rem;
    margin-bottom: 20px;
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.9;
}

.timeline {
    position: relative;
    padding-left: 30px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 8px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border);
}

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

.timeline-item::before {
    content: '';
    position: absolute;
    left: -26px;
    top: 6px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--primary);
    border: 3px solid var(--bg);
}

.timeline-item .year {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.timeline-item h4 {
    margin: 4px 0;
    font-size: 1.05rem;
}

.timeline-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* 联系方式 */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 20px;
    margin-top: 40px;
}

.contact-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    text-align: center;
    transition: var(--transition);
}

.contact-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.contact-card .contact-icon {
    font-size: 2rem;
    margin-bottom: 12px;
    display: block;
}

.contact-card h4 {
    font-size: 0.95rem;
    margin-bottom: 6px;
}

.contact-card p {
    color: var(--text-secondary);
    font-size: 0.88rem;
}

/* ============================================
   页脚
   ============================================ */
.site-footer {
    background: linear-gradient(135deg, #1e293b, #0f172a);
    color: rgba(255,255,255,0.7);
    padding: 60px 24px 30px;
    margin-top: 80px;
}

.footer-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
}

.footer-brand h3 {
    color: white;
    font-size: 1.3rem;
    margin-bottom: 14px;
}

.footer-brand p {
    font-size: 0.9rem;
    line-height: 1.8;
}

.footer-col h4 {
    color: white;
    font-size: 1rem;
    margin-bottom: 18px;
}

.footer-col ul {
    list-style: none;
}

.footer-col li {
    margin-bottom: 10px;
}

.footer-col a {
    color: rgba(255,255,255,0.6);
    font-size: 0.9rem;
    transition: var(--transition);
}

.footer-col a:hover {
    color: white;
}

.footer-bottom {
    max-width: 1200px;
    margin: 40px auto 0;
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    flex-wrap: wrap;
    gap: 12px;
}

.social-links {
    display: flex;
    gap: 12px;
}

.social-links a {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background: rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    transition: var(--transition);
}

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

/* ============================================
   滚动条 & 选择
   ============================================ */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg);
}

::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

::selection {
    background: rgba(79,70,229,0.2);
}

/* ============================================
   响应式设计 (CSS3 Media Queries)
   ============================================ */
@media (max-width: 900px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }

    .hero-text h1 {
        font-size: 2.2rem;
    }

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

    .hero-visual {
        order: -1;
    }

    .avatar-wrapper {
        width: 220px;
        height: 220px;
    }

    .avatar-circle {
        width: 180px;
        height: 180px;
        font-size: 4rem;
    }

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

    .footer-inner {
        grid-template-columns: 1fr 1fr;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 16px;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow);
    }

    .nav-links.open {
        display: flex;
    }

    .menu-toggle {
        display: flex;
    }

    .stats-bar {
        flex-wrap: wrap;
        gap: 24px;
    }

    .file-list-header,
    .file-list-row {
        grid-template-columns: 40px 1fr 100px;
    }

    .file-list-header .col-size,
    .file-list-header .col-date,
    .file-list-row .col-size,
    .file-list-row .col-date {
        display: none;
    }
}

@media (max-width: 600px) {
    main {
        padding: 84px 16px 40px;
    }

    .section-header h2 {
        font-size: 1.6rem;
    }

    .hero-text h1 {
        font-size: 1.8rem;
    }

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

    .footer-inner {
        grid-template-columns: 1fr;
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }

    .disclaimer-card {
        padding: 24px;
    }

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

/* ============================================
   深色模式 (CSS3 prefers-color-scheme)
   ============================================ */
@media (prefers-color-scheme: dark) {
    body.auto-dark {
        --bg: #0f172a;
        --bg-card: #1e293b;
        --text: #e2e8f0;
        --text-secondary: #94a3b8;
        --border: #334155;
    }

    body.auto-dark .navbar {
        background: rgba(15,23,42,0.92);
        border-bottom-color: #334155;
    }

    body.auto-dark .nav-links a {
        color: #94a3b8;
    }
}

/* 手动深色模式 */
body.dark-mode {
    --bg: #0f172a;
    --bg-card: #1e293b;
    --text: #e2e8f0;
    --text-secondary: #94a3b8;
    --border: #334155;
}

body.dark-mode .navbar {
    background: rgba(15,23,42,0.95);
    border-bottom-color: #334155;
}

body.dark-mode .nav-links a {
    color: #94a3b8;
}

body.dark-mode .nav-links a:hover,
body.dark-mode .nav-links a.active {
    color: var(--primary-light);
    background: rgba(129,140,248,0.1);
}

body.dark-mode .view-toggle {
    background: #334155;
    border-color: #475569;
}

body.dark-mode .view-toggle button.active {
    background: #1e293b;
}

/* 打印样式 */
@media print {
    .navbar, .site-footer, .hero-buttons, .file-toolbar, .video-filters {
        display: none !important;
    }

    main {
        padding-top: 20px;
    }

    .section {
        display: block !important;
        page-break-after: always;
    }
}