```css
/* =========================================================
   免费高清视频网 - 完整样式表
   UI风格：深邃蓝影 + 毛玻璃质感 + 渐变光效
   ========================================================= */

/* ---------- 核心变量与主题 ---------- */
:root {
  --bg-primary: #f0f4fa;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-nav: rgba(11, 26, 47, 0.92);
  --bg-footer: #0b1a2f;
  --bg-hero-start: #0b1a2f;
  --bg-hero-end: #1e3a5f;
  --text-primary: #1f2937;
  --text-secondary: #334155;
  --text-heading: #0f172a;
  --text-nav: #f8fafc;
  --text-footer: #cbd5e1;
  --text-muted: #64748b;
  --accent: #0369a1;
  --accent-hover: #075985;
  --accent-glow: rgba(3, 105, 161, 0.25);
  --accent-light: #38bdf8;
  --border-light: rgba(148, 163, 184, 0.25);
  --shadow-sm: 0 4px 16px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 8px 30px rgba(15, 23, 42, 0.1);
  --shadow-lg: 0 20px 50px rgba(15, 23, 42, 0.18);
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 32px;
  --backdrop-blur: blur(18px) saturate(180%);
  --transition-smooth: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --glass-bg: rgba(255, 255, 255, 0.55);
  --glass-border: rgba(255, 255, 255, 0.4);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
  --hero-text-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
  --gradient-text: linear-gradient(135deg, #7dd3fc 0%, #38bdf8 50%, #818cf8 100%);
  --gradient-hero: linear-gradient(145deg, #0b1a2f 0%, #1e3a5f 60%, #2a4a6f 100%);
  --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.9) 0%, rgba(240,245,255,0.7) 100%);
  --gradient-accent: linear-gradient(135deg, #0369a1, #0ea5e9);
}

/* 暗色模式 */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-primary: #0f172a;
    --bg-card: rgba(30, 41, 59, 0.85);
    --bg-nav: rgba(2, 6, 23, 0.95);
    --bg-footer: #020617;
    --bg-hero-start: #020617;
    --bg-hero-end: #1e293b;
    --text-primary: #e2e8f0;
    --text-secondary: #cbd5e1;
    --text-heading: #f1f5f9;
    --text-muted: #94a3b8;
    --border-light: rgba(148, 163, 184, 0.2);
    --shadow-sm: 0 4px 16px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 20px 50px rgba(0, 0, 0, 0.6);
    --glass-bg: rgba(30, 41, 59, 0.6);
    --glass-border: rgba(148, 163, 184, 0.2);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    --accent: #38bdf8;
    --accent-hover: #7dd3fc;
    --accent-glow: rgba(56, 189, 248, 0.3);
    --gradient-card: linear-gradient(145deg, rgba(30,41,59,0.9) 0%, rgba(15,23,42,0.8) 100%);
    --gradient-hero: linear-gradient(145deg, #020617 0%, #0f172a 50%, #1e293b 100%);
  }
}

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

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

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.7;
  font-size: 16px;
  overflow-x: hidden;
  transition: background-color 0.4s ease, color 0.4s ease;
  background-image: 
    radial-gradient(circle at 20% 20%, rgba(56, 189, 248, 0.05) 0%, transparent 50%),
    radial-gradient(circle at 80% 0%, rgba(129, 140, 248, 0.05) 0%, transparent 50%);
  background-attachment: fixed;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.3;
  margin-top: 0;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(2.2rem, 5vw, 3.2rem); }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.2rem); border-left: 5px solid var(--accent); padding-left: 0.9rem; }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.1rem; }

p {
  color: var(--text-primary);
  margin-bottom: 1rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease, text-shadow 0.3s ease;
  position: relative;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: none;
  text-shadow: 0 0 20px var(--accent-glow);
}

img, svg {
  max-width: 100%;
  height: auto;
  display: block;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
}

section {
  position: relative;
  padding: 40px 0;
}

/* ---------- 导航栏 ---------- */
.navbar {
  background: var(--bg-nav);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  color: var(--text-nav);
  padding: 14px 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.35);
  transition: all 0.4s ease;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: #ffffff;
  letter-spacing: 0.5px;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
  transition: transform 0.3s ease;
}

.logo:hover {
  transform: scale(1.05);
}

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

.nav-links a {
  color: var(--text-nav);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
  padding: 4px 0;
  transition: all 0.3s ease;
}

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

.nav-links a:hover {
  color: var(--accent-light);
  text-shadow: 0 0 20px var(--accent-glow);
}

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

.search-box {
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 50px;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.search-box:focus-within {
  background: rgba(255, 255, 255, 0.2);
  border-color: var(--accent-light);
  box-shadow: 0 0 20px rgba(56, 189, 248, 0.2);
}

.search-box input {
  background: transparent;
  border: none;
  color: white;
  outline: none;
  width: 160px;
  font-size: 0.9rem;
  transition: width 0.3s ease;
}

.search-box input::placeholder {
  color: rgba(255, 255, 255, 0.7);
}

.search-box input:focus {
  width: 200px;
}

.search-box button {
  background: none;
  border: none;
  color: white;
  cursor: pointer;
  font-size: 1rem;
  transition: transform 0.3s ease;
}

.search-box button:hover {
  transform: scale(1.2);
}

/* ---------- 按钮 ---------- */
.btn-primary {
  background: var(--gradient-accent);
  color: #ffffff !important;
  padding: 14px 32px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 1rem;
  display: inline-block;
  border: none;
  cursor: pointer;
  transition: all 0.35s ease;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(3, 105, 161, 0.35);
}

.btn-primary::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-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(3, 105, 161, 0.5);
  color: #ffffff !important;
}

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

.btn-primary:active {
  transform: translateY(-1px);
}

/* ---------- Hero 区域 ---------- */
.hero {
  background: var(--gradient-hero);
  color: white;
  padding: 80px 0 100px;
  position: relative;
  overflow: hidden;
  border-radius: 0 0 60px 60px;
  margin-bottom: 40px;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.15) 0%, transparent 70%);
  animation: heroGlow 8s ease-in-out infinite alternate;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(129, 140, 248, 0.1) 0%, transparent 70%);
  animation: heroGlow 6s ease-in-out infinite alternate-reverse;
}

@keyframes heroGlow {
  0% { transform: scale(1); opacity: 0.8; }
  100% { transform: scale(1.2); opacity: 1; }
}

.hero .container {
  position: relative;
  z-index: 2;
}

.hero h1 {
  color: #ffffff;
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  margin-bottom: 16px;
  text-shadow: var(--hero-text-shadow);
  animation: fadeInUp 0.8s ease-out;
}

.hero p {
  color: #e2e8f0;
  font-size: clamp(1rem, 2vw, 1.3rem);
  margin-bottom: 32px;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero .btn-primary {
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

.hero-stats {
  margin-top: 40px;
  display: flex;
  gap: 48px;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease-out 0.6s both;
}

.stat-item {
  text-align: center;
  padding: 20px 28px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-md);
  backdrop-filter: blur(10px);
  transition: all 0.3s ease;
}

.stat-item:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: translateY(-5px);
}

.stat-number {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent-light);
  display: block;
  margin-bottom: 4px;
  text-shadow: 0 0 30px rgba(56, 189, 248, 0.3);
}

.stat-label {
  font-size: 0.9rem;
  color: #cbd5e1;
  opacity: 0.9;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 卡片通用 ---------- */
.card {
  background: var(--gradient-card);
  backdrop-filter: var(--backdrop-blur);
  -webkit-backdrop-filter: var(--backdrop-blur);
  border-radius: var(--radius-md);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--glass-border);
  transition: var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-accent);
  opacity: 0;
  transition: opacity 0.4s ease;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: var(--accent);
}

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

.card h2, .card h3 {
  margin-bottom: 16px;
  position: relative;
}

.card p {
  margin-bottom: 12px;
}

/* ---------- 网格布局 ---------- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

/* ---------- 区块标题 ---------- */
.section-title {
  margin-top: 60px;
  margin-bottom: 32px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 20px;
  width: 40px;
  height: 3px;
  background: var(--gradient-accent);
  border-radius: 3px;
}

/* ---------- 文章卡片 ---------- */
article.card {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

article.card h3 {
  font-size: 1.2rem;
  line-height: 1.4;
  transition: color 0.3s ease;
}

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

.article-desc {
  color: var(--text-secondary);
  flex-grow: 1;
  font-size: 0.95rem;
}

article.card span {
  color: var(--text-muted);
  font-size: 0.85rem;
}

article.card a {
  align-self: flex-start;
  font-weight: 600;
  color: var(--accent);
  position: relative;
  padding-right: 20px;
}

article.card a::after {
  content: '→';
  position: absolute;
  right: 0;
  transition: transform 0.3s ease;
}

article.card a:hover::after {
  transform: translateX(5px);
}

/* ---------- FAQ 样式 ---------- */
.faq-item {
  border-bottom: 1px solid var(--border-light);
  padding: 20px 0;
  transition: all 0.3s ease;
}

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

.faq-question {
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--text-heading);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: color 0.3s ease;
  padding: 8px 0;
}

.faq-question::after {
  content: '+';
  font-size: 1.5rem;
  color: var(--accent);
  transition: transform 0.3s ease;
  margin-left: 16px;
}

.faq-item.active .faq-question::after {
  transform: rotate(45deg);
}

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

.faq-answer {
  margin-top: 12px;
  color: var(--text-secondary);
  line-height: 1.8;
  animation: fadeIn 0.4s ease;
}

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

/* ---------- HowTo 教程 ---------- */
#howto .card ol {
  padding-left: 24px;
  margin: 16px 0;
}

#howto .card ol li {
  margin-bottom: 8px;
  padding: 8px 16px;
  background: rgba(56, 189, 248, 0.05);
  border-radius: 8px;
  border-left: 3px solid var(--accent);
  transition: all 0.3s ease;
}

#howto .card ol li:hover {
  background: rgba(56, 189, 248, 0.1);
  transform: translateX(5px);
}

/* ---------- 联系我们 ---------- */
#contact .card {
  background: var(--glass-bg);
  backdrop-filter: var(--backdrop-blur);
  -webkit-backdrop-filter: var(--backdrop-blur);
}

#contact .card h3 {
  color: var(--accent);
  font-size: 1.1rem;
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

#contact .card p {
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-light);
}

#contact .card p:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--bg-footer);
  color: var(--text-footer);
  padding: 60px 0 40px;
  margin-top: 80px;
  position: relative;
  overflow: hidden;
}

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

.footer h4 {
  color: #ffffff;
  margin-bottom: 20px;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  position: relative;
  padding-bottom: 10px;
}

.footer h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 30px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
}

.footer a {
  color: #9ab3cf;
  transition: all 0.3s ease;
}

.footer a:hover {
  color: var(--accent-light);
  text-shadow: 0 0 15px rgba(56, 189, 248, 0.3);
}

.footer .grid-4 > div {
  padding: 0 20px;
}

.footer .container > div:last-child {
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.85rem;
  text-align: center;
  color: var(--text-muted);
}

/* ---------- 返回顶部 ---------- */
#backToTop {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--gradient-accent);
  color: white;
  border: none;
  border-radius: 50%;
  width: 52px;
  height: 52px;
  font-size: 24px;
  cursor: pointer;
  box-shadow: 0 8px 30px rgba(3, 105, 161, 0.4);
  z-index: 999;
  transition: all 0.4s ease;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
}

#backToTop.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

#backToTop:hover {
  transform: translateY(-5px) scale(1.1);
  box-shadow: 0 12px 40px rgba(3, 105, 161, 0.6);
}

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

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

/* 延迟动画 */
.reveal:nth-child(2) { transition-delay: 0.1s; }
.reveal:nth-child(3) { transition-delay: 0.2s; }
.reveal:nth-child(4) { transition-delay: 0.3s; }
.reveal:nth-child(5) { transition-delay: 0.4s; }
.reveal:nth-child(6) { transition-delay: 0.5s; }
.reveal:nth-child(7) { transition-delay: 0.6s; }
.reveal:nth-child(8) { transition-delay: 0.7s; }
.reveal:nth-child(9) { transition-delay: 0.8s; }
.reveal:nth-child(10) { transition-delay: 0.9s; }

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

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

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--accent), var(--accent-hover));
  border-radius: 10px;
  border: 2px solid var(--bg-primary);
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(180deg, var(--accent-hover), var(--accent));
}

/* ---------- 选择文本样式 ---------- */
::selection {
  background: var(--accent);
  color: white;
  text-shadow: none;
}

/* ---------- 响应式适配 ---------- */
@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .nav-links {
    gap: 20px;
  }
}

@media (max-width: 768px) {
  body {
    font-size: 15px;
  }
  
  .container {
    padding: 0 16px;
  }
  
  .navbar {
    padding: 12px 0;
  }
  
  .navbar .container {
    flex-wrap: wrap;
    gap: 12px;
  }
  
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-nav);
    flex-direction: column;
    padding: 20px;
    gap: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
  }
  
  .nav-links.show {
    display: flex;
    animation: slideDown 0.4s ease;
  }
  
  @keyframes slideDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
  }
  
  .search-box {
    width: 100%;
    order: 3;
  }
  
  .search-box input {
    flex: 1;
    width: auto;
  }
  
  .search-box input:focus {
    width: auto;
  }
  
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  
  .hero {
    padding: 60px 0 80px;
    border-radius: 0 0 40px 40px;
  }
  
  .hero-stats {
    flex-direction: column;
    gap: 16px;
  }
  
  .stat-item {
    padding: 16px 20px;
  }
  
  .card {
    padding: 24px;
  }
  
  .section-title {
    margin-top: 40px;
  }
  
  #backToTop {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    font-size: 20px;
  }
  
  .footer {
    padding: 40px 0 30px;
  }
  
  .footer .grid-4 {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
  
  .footer .grid-4 > div {
    padding: 0;
  }
}

@media (max-width: 480px) {
  h1 { font-size: 1.8rem; }
  h2 { font-size: 1.4rem; }
  
  .logo {
    font-size: 1.2rem;
  }
  
  .hero {
    padding: 40px 0 60px;
  }
  
  .hero p {
    font-size: 0.95rem;
  }
  
  .hero .btn-primary {
    padding: 12px 24px;
    font-size: 0.9rem;
  }
  
  .footer .grid-4 {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  
  .card {
    padding: 20px;
    border-radius: var(--radius-sm);
  }
}

/* ---------- 打印样式 ---------- */
@media print {
  .navbar, .footer, #backToTop, .search-box {
    display: none !important;
  }
  
  body {
    background: white;
    color: black;
    font-size: 12pt;
  }
  
  .card {
    box-shadow: none;
    border: 1px solid #ddd;
    break-inside: avoid;
  }
  
  .hero {
    background: white;
    color: black;
    border-radius: 0;
  }
  
  .hero h1, .hero p {
    color: black;
    text-shadow: none;
  }
}

/* ---------- 无障碍与可读性增强 ---------- */
@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;
  }
}

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

/* 高对比度文本 */
.card p, .faq-answer, .article-desc {
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 链接下划线动画 */
.nav-links a, .footer a {
  text-decoration: none;
  position: relative;
}

.nav-links a::before {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--accent-light);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.3s ease;
}

.nav-links a:hover::before {
  transform: scaleX(1);
  transform-origin: left;
}

/* 卡片内链接 */
.card a {
  font-weight: 600;
  position: relative;
}

/* 数字统计动画特殊效果 */
.stat-number {
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--accent-light), #818cf8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 英雄区域渐变文字 */
.hero h1 {
  background: linear-gradient(135deg, #ffffff 0%, #e0f2fe 50%, #bae6fd 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 暗色模式下的特殊调整 */
@media (prefers-color-scheme: dark) {
  .card {
    background: var(--glass-bg);
  }
  
  .search-box {
    background: rgba(255, 255, 255, 0.05);
  }
  
  .search-box input {
    color: var(--text-primary);
  }
  
  .search-box input::placeholder {
    color: var(--text-muted);
  }
  
  .search-box button {
    color: var(--text-primary);
  }
}
```