```css
/* ===== 精选视频片库 - 完整样式表 ===== */
/* 风格：现代影视媒体风 - 深色渐变 + 玻璃拟态 + 霓虹点缀 */

/* ---------- CSS变量与主题系统 ---------- */
:root {
  /* 明亮主题 */
  --bg: #0f0f1a;
  --bg-soft: #1a1a2e;
  --bg-card: rgba(255, 255, 255, 0.06);
  --bg-glass: rgba(20, 20, 40, 0.7);
  --text-primary: #e8e8f0;
  --text-secondary: #a0a0b8;
  --text-heading: #ffffff;
  --text-link: #7aa2ff;
  --text-btn: #ffffff;
  --border-color: rgba(255, 255, 255, 0.12);
  --card-bg: rgba(255, 255, 255, 0.05);
  --nav-bg: rgba(15, 15, 26, 0.85);
  --footer-bg: #0a0a14;
  --footer-text: #c0c0d0;
  --btn-bg: linear-gradient(135deg, #6c5ce7, #a855f7);
  --btn-bg-solid: #7c3aed;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-hover: 0 12px 40px rgba(124, 58, 237, 0.3);
  --glow: 0 0 20px rgba(124, 58, 237, 0.3);
  --hero-gradient: linear-gradient(135deg, #1a1a3e 0%, #4a1a7a 50%, #7c3aed 100%);
  --accent: #a855f7;
  --accent-light: #c084fc;
  --success: #10b981;
  --warning: #f59e0b;
  --radius: 16px;
  --radius-sm: 10px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
  /* 暗黑主题（增强版） */
  --bg: #08080f;
  --bg-soft: #12121f;
  --bg-card: rgba(255, 255, 255, 0.04);
  --bg-glass: rgba(10, 10, 20, 0.8);
  --text-primary: #d0d0e0;
  --text-secondary: #8888a0;
  --text-heading: #ffffff;
  --text-link: #93c5fd;
  --border-color: rgba(255, 255, 255, 0.08);
  --card-bg: rgba(20, 20, 40, 0.5);
  --nav-bg: rgba(8, 8, 15, 0.9);
  --footer-bg: #05050a;
  --footer-text: #a0a0b8;
  --btn-bg: linear-gradient(135deg, #4a1a7a, #7c3aed);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.6);
  --shadow-hover: 0 12px 48px rgba(124, 58, 237, 0.4);
  --glow: 0 0 30px rgba(124, 58, 237, 0.4);
  --hero-gradient: linear-gradient(135deg, #0a0a1a 0%, #2a1040 50%, #4a1a7a 100%);
}

/* ---------- 基础重置与全局样式 ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg);
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.8;
  transition: background-color 0.4s ease, color 0.4s ease;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 20% 20%, rgba(124, 58, 237, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(168, 85, 247, 0.06) 0%, transparent 50%);
  background-attachment: fixed;
}

/* 自定义滚动条 */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  border-radius: 20px;
  border: 2px solid var(--bg);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-light);
}

/* ---------- 排版 ---------- */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  margin-bottom: 1.5rem;
  background: linear-gradient(135deg, #fff, var(--accent-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  filter: drop-shadow(0 2px 10px rgba(124, 58, 237, 0.3));
}

h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
  margin: 3rem 0 1.5rem;
  padding-bottom: 0.75rem;
  position: relative;
  display: inline-block;
}

h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  border-radius: 3px;
}

h3 {
  font-size: clamp(1.2rem, 2.5vw, 1.6rem);
  margin: 2rem 0 1rem;
}

h4 {
  font-size: 1.15rem;
  margin: 1.5rem 0 0.75rem;
}

p {
  margin-bottom: 1.2rem;
  color: var(--text-primary);
  line-height: 1.9;
}

a {
  color: var(--text-link);
  text-decoration: none;
  transition: color 0.3s ease;
}

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

strong {
  color: var(--text-heading);
  font-weight: 600;
}

/* ---------- 布局容器 ---------- */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }
}

/* ---------- 导航栏 ---------- */
.navbar {
  position: sticky;
  top: 0;
  background: var(--nav-bg);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  max-width: 1280px;
  margin: 0 auto;
  gap: 1rem;
}

.logo a {
  font-size: 1.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.5px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo a::before {
  content: '▶';
  font-size: 1.2rem;
  -webkit-text-fill-color: var(--accent);
}

.nav-menu {
  display: flex;
  gap: 2rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-menu a {
  color: var(--text-primary);
  font-weight: 500;
  padding: 0.5rem 0;
  position: relative;
  font-size: 0.95rem;
  transition: color 0.3s ease;
}

.nav-menu a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.3s ease;
}

.nav-menu a:hover {
  color: var(--accent-light);
}

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

.nav-actions {
  display: flex;
  gap: 0.75rem;
  align-items: center;
}

.theme-toggle, .search-btn, .menu-toggle {
  background: var(--bg-soft);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 0.4rem 1rem;
  border-radius: 30px;
  cursor: pointer;
  font-weight: 500;
  font-size: 0.9rem;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.theme-toggle:hover, .search-btn:hover, .menu-toggle:hover {
  border-color: var(--accent);
  color: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: var(--glow);
}

.menu-toggle {
  display: none;
  font-size: 1.2rem;
  padding: 0.4rem 0.8rem;
}

/* 移动端菜单 */
@media (max-width: 768px) {
  .nav-menu {
    display: none;
    flex-direction: column;
    width: 100%;
    background: var(--nav-bg);
    padding: 1.5rem 0;
    border-top: 1px solid var(--border-color);
    gap: 0.5rem;
    backdrop-filter: blur(20px);
  }
  
  .nav-menu.active {
    display: flex;
  }
  
  .nav-menu a {
    padding: 0.75rem 2rem;
    font-size: 1rem;
  }
  
  .menu-toggle {
    display: block;
  }
  
  .nav-container {
    flex-wrap: wrap;
  }
  
  .nav-actions {
    order: 3;
  }
}

/* ---------- 搜索框 ---------- */
.search-box {
  display: flex;
  gap: 0.75rem;
  margin: 2rem 0;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.search-box input {
  flex: 1;
  padding: 0.8rem 1.5rem;
  border-radius: 50px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 1rem;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.search-box input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.1);
}

.search-box input::placeholder {
  color: var(--text-secondary);
}

.search-box button {
  background: var(--btn-bg);
  color: var(--text-btn);
  border: none;
  padding: 0.8rem 2rem;
  border-radius: 50px;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(124, 58, 237, 0.3);
}

.search-box button:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(124, 58, 237, 0.4);
}

/* ---------- Hero Banner ---------- */
.hero {
  background: var(--hero-gradient);
  color: white;
  padding: 4rem 3rem;
  border-radius: 24px;
  margin: 2.5rem 0;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--border-color);
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 80%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
  transform: rotate(30deg);
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 60%;
  height: 150%;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.2) 0%, transparent 70%);
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-content h1 {
  color: white;
  -webkit-text-fill-color: white;
  font-size: clamp(2rem, 5vw, 3.5rem);
  margin-bottom: 1rem;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.hero-content p {
  color: rgba(255, 255, 255, 0.95);
  font-size: 1.2rem;
  max-width: 700px;
  line-height: 1.8;
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.2);
}

.hero-badge {
  display: inline-block;
  background: rgba(255, 255, 255, 0.15);
  padding: 0.4rem 1.2rem;
  border-radius: 50px;
  font-weight: 500;
  margin-bottom: 1.5rem;
  color: white;
  font-size: 0.9rem;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  letter-spacing: 0.5px;
}

/* ---------- 卡片网格 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: var(--transition);
  backdrop-filter: blur(10px);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(124, 58, 237, 0.3);
}

.card:hover::before {
  opacity: 1;
}

.card h3 {
  margin-top: 0;
  font-size: 1.3rem;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ---------- 表格 ---------- */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border-color);
}

th, td {
  padding: 0.9rem 1.2rem;
  border: 1px solid var(--border-color);
  text-align: left;
}

th {
  background: var(--bg-soft);
  color: var(--text-heading);
  font-weight: 600;
  font-size: 0.95rem;
}

td {
  color: var(--text-primary);
  font-size: 0.95rem;
}

tr:hover {
  background: rgba(124, 58, 237, 0.05);
}

/* ---------- FAQ ---------- */
.faq-item {
  border-bottom: 1px solid var(--border-color);
  padding: 1.2rem 0;
  transition: background 0.3s ease;
}

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

.faq-question {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--text-heading);
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  transition: color 0.3s ease;
  padding: 0.5rem 0;
}

.faq-question:hover {
  color: var(--accent-light);
}

.faq-question span {
  font-size: 1.5rem;
  color: var(--accent);
  transition: transform 0.3s ease;
  display: inline-block;
}

.faq-question span.open {
  transform: rotate(45deg);
}

.faq-answer {
  margin-top: 0.75rem;
  color: var(--text-primary);
  line-height: 1.8;
  padding-right: 2rem;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- 按钮 ---------- */
.btn {
  background: var(--btn-bg);
  color: var(--text-btn);
  padding: 0.8rem 2rem;
  border-radius: 50px;
  border: none;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  display: inline-block;
  text-align: center;
  transition: var(--transition);
  box-shadow: 0 4px 15px rgba(124, 58, 237, 0.3);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transition: left 0.5s ease;
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(124, 58, 237, 0.4);
  color: white;
}

.btn:hover::before {
  left: 100%;
}

/* ---------- 页脚 ---------- */
footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 3rem 0;
  margin-top: 4rem;
  border-top: 1px solid var(--border-color);
  position: relative;
}

footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
}

footer a {
  color: var(--footer-text);
  transition: color 0.3s ease;
}

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

footer .footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  margin-bottom: 2rem;
  justify-content: center;
}

.footer-links a {
  color: var(--footer-text);
  font-size: 0.95rem;
  position: relative;
}

.footer-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--accent);
  transition: width 0.3s ease;
}

.footer-links a:hover::after {
  width: 100%;
}

.footer-copy {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 2rem;
  font-size: 0.9rem;
  text-align: center;
}

.footer-copy p {
  color: var(--footer-text);
  margin-bottom: 0.5rem;
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  padding: 1rem 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.breadcrumb span {
  color: var(--text-secondary);
}

.breadcrumb a {
  color: var(--text-link);
  transition: color 0.3s ease;
}

.breadcrumb a:hover {
  color: var(--accent-light);
}

/* ---------- 滚动动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 延迟动画 */
.reveal.delay-1 { transition-delay: 0.1s; }
.reveal.delay-2 { transition-delay: 0.2s; }
.reveal.delay-3 { transition-delay: 0.3s; }
.reveal.delay-4 { transition-delay: 0.4s; }
.reveal.delay-5 { transition-delay: 0.5s; }

/* ---------- 返回顶部 ---------- */
#backToTop {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--btn-bg);
  color: white;
  border: none;
  border-radius: 50%;
  width: 48px;
  height: 48px;
  font-size: 1.3rem;
  cursor: pointer;
  display: none;
  z-index: 999;
  box-shadow: 0 4px 20px rgba(124, 58, 237, 0.4);
  transition: var(--transition);
  backdrop-filter: blur(10px);
}

#backToTop:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 8px 30px rgba(124, 58, 237, 0.6);
}

/* ---------- 标签 ---------- */
.tag {
  background: var(--bg-soft);
  color: var(--text-primary);
  padding: 0.3rem 1rem;
  border-radius: 50px;
  border: 1px solid var(--border-color);
  font-size: 0.85rem;
  transition: var(--transition);
  cursor: pointer;
  display: inline-block;
  margin: 0.25rem;
}

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

/* ---------- 网格工具类 ---------- */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 768px) {
  .grid-2 {
    grid-template-columns: 1fr;
  }
}

/* ---------- 文本工具类 ---------- */
.text-secondary {
  color: var(--text-secondary);
}

.text-heading {
  color: var(--text-heading);
}

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

.text-gradient {
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ---------- 列表优化 ---------- */
ol, ul {
  padding-left: 1.5rem;
  margin-bottom: 1.2rem;
}

li {
  margin-bottom: 0.5rem;
  line-height: 1.8;
}

/* ---------- 区块间距 ---------- */
section {
  margin-bottom: 3rem;
  padding: 1.5rem 0;
}

section:first-of-type {
  margin-top: 1rem;
}

/* ---------- 响应式优化 ---------- */
@media (max-width: 1024px) {
  .card-grid {
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  }
  
  .hero {
    padding: 3rem 2rem;
  }
}

@media (max-width: 768px) {
  h1 {
    font-size: 1.8rem;
  }
  
  h2 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
  }
  
  h3 {
    font-size: 1.2rem;
  }
  
  .hero {
    padding: 2.5rem 1.5rem;
    border-radius: 16px;
    margin: 1.5rem 0;
  }
  
  .hero-content h1 {
    font-size: 1.8rem;
  }
  
  .hero-content p {
    font-size: 1rem;
  }
  
  .search-box {
    flex-direction: column;
    gap: 0.75rem;
  }
  
  .search-box button {
    width: 100%;
  }
  
  .card {
    padding: 1.2rem;
  }
  
  .card-grid {
    gap: 1rem;
  }
  
  .faq-question {
    font-size: 1rem;
  }
  
  #backToTop {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
    font-size: 1.1rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 12px;
  }
  
  .nav-container {
    padding: 12px;
  }
  
  .logo a {
    font-size: 1.2rem;
  }
  
  .theme-toggle, .search-btn {
    padding: 0.3rem 0.7rem;
    font-size: 0.85rem;
  }
  
  .hero {
    padding: 2rem 1rem;
  }
  
  .hero-badge {
    font-size: 0.8rem;
    padding: 0.3rem 0.8rem;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
  }
  
  .btn {
    width: 100%;
  }
  
  table {
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }
  
  .footer-links {
    gap: 1rem;
  }
}

/* ---------- 暗色模式媒体查询（自动适配） ---------- */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #08080f;
    --bg-soft: #12121f;
    --text-primary: #d0d0e0;
    --text-secondary: #8888a0;
    --text-heading: #ffffff;
    --border-color: rgba(255, 255, 255, 0.08);
  }
}

/* ---------- 打印样式 ---------- */
@media print {
  .navbar, .search-box, .hero, #backToTop, .nav-actions {
    display: none !important;
  }
  
  body {
    background: white;
    color: black;
  }
  
  .card {
    box-shadow: none;
    border: 1px solid #ddd;
  }
}

/* ---------- 性能优化 ---------- */
img, video {
  max-width: 100%;
  height: auto;
}

/* 减少动画重绘 */
* {
  -webkit-tap-highlight-color: transparent;
}

/* 平滑滚动 */
html {
  scroll-padding-top: 80px;
}

/* 焦点可见性 */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* 减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}
```