```css
/* 樱桃视频 全站样式 - 暗色优先设计 */
:root {
  --bg: #0b0f1a;
  --bg-elevated: #131a2b;
  --bg-card: #1a2333;
  --bg-hover: #223047;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-heading: #ffffff;
  --text-link: #60a5fa;
  --accent: #2563eb;
  --accent-light: #3b82f6;
  --accent-glow: rgba(37, 99, 235, 0.35);
  --border: #2a3a55;
  --border-light: #3a4a6b;
  --shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
  --shadow-hover: 0 25px 50px rgba(0, 0, 0, 0.6);
  --radius: 24px;
  --radius-sm: 14px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --gradient: linear-gradient(135deg, #1e3a8a 0%, #2563eb 50%, #7c3aed 100%);
}

[data-theme="light"] {
  --bg: #f8fafc;
  --bg-elevated: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #f1f5f9;
  --text-primary: #1e293b;
  --text-secondary: #475569;
  --text-heading: #0f172a;
  --text-link: #1d4ed8;
  --border: #e2e8f0;
  --border-light: #cbd5e1;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 15px 40px rgba(0, 0, 0, 0.12);
}

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

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

body {
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background-color 0.4s ease, color 0.4s ease;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 0.6rem;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); margin-top: 2rem; position: relative; }
h3 { font-size: clamp(1.2rem, 2vw, 1.5rem); }
h4 { font-size: 1.1rem; color: var(--text-secondary); }

p {
  margin-bottom: 1.2rem;
  color: var(--text-primary);
  font-size: 1rem;
  line-height: 1.8;
}

a {
  color: var(--text-link);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2.5rem);
  width: 100%;
}

/* ===== 导航栏 ===== */
.navbar {
  position: sticky;
  top: 0;
  background: var(--bg-elevated);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.15);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  transition: all 0.4s ease;
}

.nav-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.8rem 0;
  gap: 1rem;
}

.logo {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text-heading);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  transition: transform 0.3s ease;
}

.logo:hover {
  transform: scale(1.02);
}

.logo svg {
  width: 36px;
  height: 36px;
  filter: drop-shadow(0 2px 8px var(--accent-glow));
}

.nav-links {
  display: flex;
  gap: clamp(1rem, 2.5vw, 2.5rem);
  align-items: center;
}

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

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

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--bg-card);
  border-radius: 50px;
  padding: 0.4rem 1rem;
  border: 1px solid var(--border);
  transition: border-color 0.3s, box-shadow 0.3s;
}

.search-box:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.search-box input {
  border: none;
  background: transparent;
  padding: 0.4rem 0.6rem;
  color: var(--text-primary);
  font-size: 0.95rem;
  outline: none;
  width: clamp(100px, 15vw, 180px);
}

.search-box input::placeholder {
  color: var(--text-secondary);
  opacity: 0.7;
}

.icon-btn {
  background: var(--bg-card);
  border: 1px solid var(--border);
  cursor: pointer;
  color: var(--text-primary);
  font-size: 1.3rem;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem;
  border-radius: 50%;
  transition: all 0.3s ease;
  width: 42px;
  height: 42px;
}

.icon-btn:hover {
  background: var(--bg-hover);
  transform: rotate(15deg);
  border-color: var(--accent);
}

.mobile-menu {
  display: none;
  font-size: 1.8rem;
  cursor: pointer;
  color: var(--text-primary);
  padding: 0.3rem;
}

/* ===== Banner ===== */
.banner {
  background: var(--gradient);
  color: #fff;
  padding: clamp(3rem, 8vw, 5rem) 0;
  margin-bottom: 3rem;
  position: relative;
  overflow: hidden;
}

.banner::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 60%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
  pointer-events: none;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
}

.banner-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 2rem;
  position: relative;
  z-index: 1;
}

.banner-text {
  flex: 1 1 350px;
}

.banner-text h2 {
  color: #fff;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  margin-bottom: 1rem;
  border: none;
  text-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.banner-text p {
  color: rgba(255,255,255,0.9);
  font-size: clamp(1rem, 2vw, 1.2rem);
  max-width: 600px;
  text-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.banner-stats {
  display: flex;
  gap: clamp(1.5rem, 4vw, 3rem);
  background: rgba(255,255,255,0.1);
  padding: 1.5rem 2rem;
  border-radius: 20px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.2);
  box-shadow: 0 8px 32px rgba(0,0,0,0.2);
}

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

.stat-number {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  color: #fff;
  text-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.stat-label {
  color: rgba(255,255,255,0.8);
  font-size: 0.9rem;
  letter-spacing: 0.05em;
}

/* ===== 卡片 ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.8rem;
  margin: 2.5rem 0;
}

.card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 1.8rem;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient);
  opacity: 0;
  transition: opacity 0.3s;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
}

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

.card h3 {
  margin-bottom: 0.8rem;
  transition: color 0.3s;
}

.card:hover h3 {
  color: var(--accent-light);
}

.card p {
  color: var(--text-secondary);
  margin-bottom: 0;
}

.badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: #fff;
  font-weight: 600;
  padding: 0.3rem 1rem;
  border-radius: 30px;
  font-size: 0.8rem;
  margin-bottom: 1rem;
  box-shadow: 0 4px 12px var(--accent-glow);
}

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

.info-table th, .info-table td {
  padding: 1.2rem 1.5rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
}

.info-table th {
  background: var(--bg-elevated);
  color: var(--text-heading);
  font-weight: 700;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.info-table td {
  color: var(--text-primary);
}

.info-table tr:last-child th,
.info-table tr:last-child td {
  border-bottom: none;
}

.info-table tr:hover td {
  background: var(--bg-hover);
}

/* ===== FAQ ===== */
.faq-item {
  background: var(--bg-card);
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
  padding: 0.5rem 1.5rem;
  border: 1px solid var(--border);
  transition: border-color 0.3s, box-shadow 0.3s;
  overflow: hidden;
}

.faq-item:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 20px var(--accent-glow);
}

.faq-question {
  font-weight: 600;
  font-size: 1.1rem;
  padding: 1rem 0;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-heading);
  transition: color 0.3s;
}

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

.faq-question span {
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--accent-light);
  transition: transform 0.3s;
}

.faq-answer {
  padding-bottom: 1.2rem;
  color: var(--text-primary);
  border-top: 1px solid var(--border);
  padding-top: 0.8rem;
  line-height: 1.8;
}

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

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  height: 1px;
  background: var(--gradient);
  opacity: 0.3;
}

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

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

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 2rem;
}

.footer h4 {
  color: var(--text-heading);
  margin-bottom: 1rem;
  font-size: 1.1rem;
}

.footer p, .footer li {
  color: var(--text-secondary);
  line-height: 2;
}

.copyright {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  margin-top: 2rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* ===== 按钮 ===== */
.btn {
  background: var(--gradient);
  color: #fff;
  border: none;
  padding: 0.8rem 2rem;
  border-radius: 50px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 20px var(--accent-glow);
  display: inline-block;
  text-align: center;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--accent-glow);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--accent);
  color: var(--accent);
  box-shadow: none;
}

.btn-outline:hover {
  background: var(--accent);
  color: #fff;
}

/* ===== 返回顶部 ===== */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background: var(--gradient);
  color: #fff;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  box-shadow: 0 8px 30px var(--accent-glow);
  cursor: pointer;
  z-index: 999;
  border: none;
  transition: all 0.3s ease;
  opacity: 0;
  visibility: hidden;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-4px) scale(1.1);
}

/* ===== 滚动动画 ===== */
.fade-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 新闻卡片特殊样式 ===== */
#news .card {
  padding: 1.5rem;
}

#news .card h4 {
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
  color: var(--text-heading);
}

#news .card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

#news .card a {
  font-size: 0.9rem;
  font-weight: 600;
}

/* ===== HowTo 样式 ===== */
#howto ol {
  margin-left: 1.5rem;
  color: var(--text-primary);
  line-height: 2.2;
}

#howto ol li::marker {
  color: var(--accent);
  font-weight: 700;
}

/* ===== 友情链接 ===== */
#links p {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

#links a {
  padding: 0.5rem 1.2rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 50px;
  transition: all 0.3s ease;
}

#links a:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .banner-content {
    flex-direction: column;
    text-align: center;
  }
  
  .banner-stats {
    justify-content: center;
    width: 100%;
  }
  
  .banner-text p {
    margin: 0 auto 1.5rem;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-elevated);
    flex-direction: column;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
  }
  
  .nav-links.active {
    display: flex;
  }
  
  .nav-links a {
    padding: 0.8rem 0;
    width: 100%;
    text-align: center;
  }
  
  .mobile-menu {
    display: block;
  }
  
  .search-box input {
    width: 100px;
  }
  
  .banner-stats {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 1.5rem;
    padding: 1rem;
  }
  
  .stat-number {
    font-size: 1.8rem;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  
  .info-table {
    font-size: 0.9rem;
  }
  
  .info-table th, .info-table td {
    padding: 0.8rem 1rem;
  }
  
  h1 { font-size: 1.8rem; }
  h2 { font-size: 1.4rem; }
  
  .back-to-top {
    bottom: 1.5rem;
    right: 1.5rem;
    width: 44px;
    height: 44px;
    font-size: 1.2rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 1rem;
  }
  
  .nav-content {
    padding: 0.6rem 0;
  }
  
  .logo {
    font-size: 1.3rem;
  }
  
  .logo svg {
    width: 28px;
    height: 28px;
  }
  
  .search-box {
    display: none;
  }
  
  .banner {
    padding: 2.5rem 0;
  }
  
  .banner-stats {
    gap: 1rem;
    padding: 1rem;
  }
  
  .stat-item {
    min-width: 80px;
  }
  
  .stat-number {
    font-size: 1.5rem;
  }
  
  .stat-label {
    font-size: 0.8rem;
  }
  
  .card {
    padding: 1.2rem;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .copyright {
    font-size: 0.8rem;
  }
}

/* ===== 暗色模式过渡 ===== */
body, .navbar, .card, .faq-item, .footer, .info-table {
  transition: background-color 0.4s ease, color 0.4s ease, border-color 0.4s ease;
}

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

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

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 10px;
}

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

/* ===== 选中文本 ===== */
::selection {
  background: var(--accent);
  color: #fff;
}

/* ===== 焦点可见性 ===== */
:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ===== 性能优化 ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}
```