/* CSS变量定义 */
:root {
  /* Chrome品牌颜色 */
  --chrome-blue: #4285F4;
  --chrome-red: #EA4335;
  --chrome-yellow: #FBBC05;
  --chrome-green: #34A853;
  
  /* 中性颜色 */
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #e9ecef;
  --text-primary: #202124;
  --text-secondary: #5f6368;
  --text-tertiary: #9aa0a6;
  --border-color: #dadce0;
  
  /* 渐变色 */
  --gradient-primary: linear-gradient(135deg, var(--chrome-blue) 0%, #3367d6 100%);
  --gradient-secondary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-accent: linear-gradient(135deg, var(--chrome-red) 0%, var(--chrome-yellow) 100%);
  
  /* 阴影 */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
  
  /* 间距 */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* 边框半径 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
  
  /* 过渡效果 */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* 字体 */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-md: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  
  /* 断点 */
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
  --breakpoint-2xl: 1536px;
}

/* 深色模式变量 */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-primary: #202124;
    --bg-secondary: #2d2e30;
    --bg-tertiary: #3c3d3f;
    --text-primary: #e8eaed;
    --text-secondary: #bdc1c6;
    --text-tertiary: #9aa0a6;
    --border-color: #5f6368;
  }
}

/* 基础样式重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* 容器样式 */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* 部分标题样式 */
.section-header {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.section-header h2 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
  line-height: 1.2;
}

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

/* 按钮样式 */
.btn {
  display: inline-block;
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--radius-md);
  font-size: var(--font-size-md);
  font-weight: 600;
  text-decoration: none;
  text-align: center;
  transition: all var(--transition-normal);
  cursor: pointer;
  border: none;
  outline: none;
}

.primary-btn {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-md);
}

.primary-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.secondary-btn {
  background-color: transparent;
  color: var(--chrome-blue);
  border: 2px solid var(--chrome-blue);
}

.secondary-btn:hover {
  background-color: var(--chrome-blue);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.download-btn {
  background: var(--gradient-accent);
  color: white;
  box-shadow: var(--shadow-md);
  font-weight: 600;
}

.download-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* 导航栏样式 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  transition: all var(--transition-normal);
}

@media (prefers-color-scheme: dark) {
  .navbar {
    background-color: rgba(32, 33, 36, 0.95);
    border-bottom-color: var(--border-color);
  }
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) var(--spacing-lg);
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  text-decoration: none;
}

.chrome-logo {
  width: 40px;
  height: 40px;
}

.logo-svg {
  width: 100%;
  height: 100%;
  transition: transform var(--transition-normal);
}

.navbar-brand:hover .logo-svg {
  transform: rotate(15deg) scale(1.1);
}

.brand-name {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--text-primary);
}

.navbar-menu {
  display: flex;
  align-items: center;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: var(--spacing-xl);
  align-items: center;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  transition: all var(--transition-normal);
  position: relative;
}

.nav-links a:hover {
  color: var(--chrome-blue);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--chrome-blue);
  transition: width var(--transition-normal);
}

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

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: var(--font-size-xl);
  cursor: pointer;
}

.menu-icon {
  width: 24px;
  height: 24px;
}

/* 英雄区域样式 */
.hero {
  padding: var(--spacing-3xl) 0;
  margin-top: 80px;
  background: var(--gradient-secondary);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 30%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
  z-index: 0;
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-content {
  color: white;
}

.hero-content h1 {
  font-size: var(--font-size-5xl);
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
  line-height: 1.1;
}

.hero-content p {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-2xl);
  opacity: 0.9;
}

.hero-buttons {
  display: flex;
  gap: var(--spacing-lg);
  flex-wrap: wrap;
}

.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.browser-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
  perspective: 1000px;
}

.browser-card {
  background-color: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  transform: rotateY(0deg);
  transition: all var(--transition-normal);
  animation: float 6s ease-in-out infinite;
}

.browser-card:nth-child(2) {
  animation-delay: 1s;
}

.browser-card:nth-child(3) {
  animation-delay: 2s;
}

.browser-card:hover {
  transform: rotateY(10deg) translateY(-10px);
  box-shadow: var(--shadow-xl), 0 0 30px rgba(66, 133, 244, 0.3);
}

.browser-header {
  background-color: var(--bg-tertiary);
  padding: var(--spacing-sm);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.browser-controls {
  display: flex;
  gap: 6px;
}

.control-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.control-dot.red {
  background-color: var(--chrome-red);
}

.control-dot.yellow {
  background-color: var(--chrome-yellow);
}

.control-dot.green {
  background-color: var(--chrome-green);
}

.browser-url {
  flex: 1;
  background-color: white;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-xs);
  color: var(--text-secondary);
}

.browser-content {
  height: 150px;
  background-color: var(--bg-secondary);
  position: relative;
}

.browser-page {
  position: absolute;
  top: 20px;
  left: 20px;
  right: 20px;
  bottom: 20px;
  background: linear-gradient(135deg, var(--chrome-blue) 0%, var(--chrome-green) 100%);
  border-radius: var(--radius-sm);
}

/* 特性区域样式 */
.features {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-primary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-2xl);
}

.feature-card {
  background-color: var(--bg-secondary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: transform var(--transition-normal);
}

.feature-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

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

.feature-icon {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--spacing-lg);
  font-size: var(--font-size-2xl);
  transition: all var(--transition-normal);
}

.speed-icon {
  background: linear-gradient(135deg, var(--chrome-blue) 0%, #3367d6 100%);
  color: white;
}

.security-icon {
  background: linear-gradient(135deg, var(--chrome-red) 0%, #e53935 100%);
  color: white;
}

.sync-icon {
  background: linear-gradient(135deg, var(--chrome-green) 0%, #2e7d32 100%);
  color: white;
}

.extensions-icon {
  background: linear-gradient(135deg, var(--chrome-yellow) 0%, #f57f17 100%);
  color: white;
}

.dark-icon {
  background: linear-gradient(135deg, #666666 0%, #333333 100%);
  color: white;
}

.mobile-icon {
  background: linear-gradient(135deg, #9c27b0 0%, #673ab7 100%);
  color: white;
}

.feature-card:hover .feature-icon {
  transform: scale(1.1) rotate(15deg);
}

.icon-svg {
  width: 40px;
  height: 40px;
}

.feature-card h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.feature-card p {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 速度区域样式 */
.speed {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-secondary);
  position: relative;
  overflow: hidden;
}

.speed::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 10% 50%, rgba(66, 133, 244, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 90% 50%, rgba(66, 133, 244, 0.1) 0%, transparent 50%);
  z-index: 0;
}

.speed .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
  position: relative;
  z-index: 1;
}

.speed-content h2 {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
}

.speed-content p {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-2xl);
  color: var(--text-secondary);
}

.speed-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-2xl);
}

.stat-item {
  text-align: center;
  padding: var(--spacing-lg);
  background-color: var(--bg-primary);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.stat-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.stat-number {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  color: var(--chrome-blue);
  margin-bottom: var(--spacing-xs);
}

.stat-label {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.speed-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.speed-meter {
  width: 300px;
  height: 300px;
  position: relative;
}

.meter-bg {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: conic-gradient(
    var(--chrome-red) 0deg 60deg,
    var(--chrome-yellow) 60deg 120deg,
    var(--chrome-green) 120deg 360deg
  );
  display: flex;
  align-items: center;
  justify-content: center;
  animation: rotate 3s linear infinite;
}

.meter-progress {
  position: absolute;
  top: 10px;
  left: 10px;
  right: 10px;
  bottom: 10px;
  border-radius: 50%;
  background-color: var(--bg-primary);
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.speed-value {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  color: var(--chrome-blue);
}

.speed-unit {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
}

/* 安全区域样式 */
.security {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-primary);
}

.security .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
}

.security-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.security-shield {
  position: relative;
  width: 300px;
  height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.shield-svg {
  width: 200px;
  height: 200px;
  fill: var(--chrome-blue);
  animation: pulse 2s ease-in-out infinite;
}

.shield-glow {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(66, 133, 244, 0.4) 0%, transparent 70%);
  animation: glow 2s ease-in-out infinite;
}

.security-content h2 {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
}

.security-content p {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-2xl);
  color: var(--text-secondary);
}

.security-features {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.security-item {
  display: flex;
  gap: var(--spacing-lg);
  align-items: flex-start;
  padding: var(--spacing-lg);
  background-color: var(--bg-secondary);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

.security-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.security-icon {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background-color: var(--chrome-blue);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.security-item h3 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.security-item p {
  font-size: var(--font-size-md);
  color: var(--text-secondary);
  margin: 0;
  line-height: 1.6;
}

/* 关于区域样式 */
.about {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-secondary);
}

.about-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.about-content p {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-2xl);
  line-height: 1.6;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-2xl);
  margin-top: var(--spacing-2xl);
}

.stat-card {
  background-color: var(--bg-primary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.stat-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.stat-card .stat-number {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  color: var(--chrome-blue);
  margin-bottom: var(--spacing-sm);
}

.stat-card .stat-label {
  font-size: var(--font-size-md);
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* CTA区域样式 */
.cta {
  padding: var(--spacing-3xl) 0;
  background: var(--gradient-primary);
  position: relative;
  overflow: hidden;
}

.cta::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
  z-index: 0;
}

.cta .container {
  position: relative;
  z-index: 1;
}

.cta-content {
  text-align: center;
  color: white;
  max-width: 600px;
  margin: 0 auto;
}

.cta-content h2 {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
}

.cta-content p {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-2xl);
  opacity: 0.9;
}

/* 下载英雄区域样式 */
.download-hero {
  padding: var(--spacing-3xl) 0;
  margin-top: 80px;
  background: var(--gradient-primary);
  color: white;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.download-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 30% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 70% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
  z-index: 0;
}

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

.download-hero h1 {
  font-size: var(--font-size-5xl);
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
}

.download-hero p {
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-2xl);
  opacity: 0.9;
}

.platform-detection {
  margin-top: var(--spacing-2xl);
  background-color: rgba(255, 255, 255, 0.1);
  padding: var(--spacing-lg);
  border-radius: var(--radius-lg);
  display: inline-block;
  backdrop-filter: blur(10px);
}

.platform-detection p {
  margin-bottom: var(--spacing-md);
  font-size: var(--font-size-md);
}

.detected-platform {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  font-size: var(--font-size-lg);
  font-weight: 600;
}

.platform-icon {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background-color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--chrome-blue);
}

/* 平台下载区域样式 */
.platform-downloads {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-primary);
}

.platform-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-2xl);
}

.platform-card {
  background-color: var(--bg-secondary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  text-align: center;
  border: 2px solid transparent;
}

.platform-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
  border-color: var(--chrome-blue);
}

.platform-icon {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--spacing-lg);
  font-size: var(--font-size-2xl);
}

.windows-icon {
  background-color: #0078d7;
  color: white;
}

.mac-icon {
  background-color: #007aff;
  color: white;
}

.linux-icon {
  background-color: #ff6b6b;
  color: white;
}

.android-icon {
  background-color: #34a853;
  color: white;
}

.ios-icon {
  background-color: #007aff;
  color: white;
}

.platform-card h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

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

.platform-download-btn {
  width: 100%;
  margin-top: var(--spacing-md);
}

/* 系统要求区域样式 */
.system-requirements {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-secondary);
}

.requirements-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-2xl);
}

.requirement-card {
  background-color: var(--bg-primary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.requirement-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.requirement-card h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
  border-bottom: 2px solid var(--chrome-blue);
  padding-bottom: var(--spacing-md);
}

.requirement-card ul {
  list-style: none;
}

.requirement-card li {
  padding: var(--spacing-sm) 0;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-color);
  position: relative;
  padding-left: var(--spacing-2xl);
}

.requirement-card li::before {
  content: '•';
  position: absolute;
  left: var(--spacing-lg);
  color: var(--chrome-blue);
  font-weight: bold;
}

/* FAQ区域样式 */
.faq {
  padding: var(--spacing-3xl) 0;
  background-color: var(--bg-primary);
}

.faq-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-2xl);
}

.faq-item {
  background-color: var(--bg-secondary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.faq-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.faq-question {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-question::after {
  content: '+';
  font-size: var(--font-size-xl);
  font-weight: 300;
  transition: transform var(--transition-normal);
}

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

.faq-answer {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 页脚样式 */
.footer {
  background-color: var(--bg-secondary);
  padding: var(--spacing-3xl) 0;
  border-top: 1px solid var(--border-color);
}

.footer .container {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2xl);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-3xl);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-2xl);
}

.link-group h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
}

.link-group ul {
  list-style: none;
}

.link-group li {
  margin-bottom: var(--spacing-md);
}

.link-group a {
  text-decoration: none;
  color: var(--text-secondary);
  transition: color var(--transition-normal);
}

.link-group a:hover {
  color: var(--chrome-blue);
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: var(--spacing-2xl);
  text-align: center;
  color: var(--text-secondary);
}

.footer-bottom p {
  margin-bottom: var(--spacing-sm);
  font-size: var(--font-size-sm);
}

/* 动画定义 */
@keyframes float {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-20px);
  }
}

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

@keyframes pulse {
  0%, 100% {
    transform: scale(1);
    opacity: 1;
  }
  50% {
    transform: scale(1.1);
    opacity: 0.8;
  }
}

@keyframes glow {
  0%, 100% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 0.6;
  }
  50% {
    transform: translate(-50%, -50%) scale(1.1);
    opacity: 0.8;
  }
}

/* 响应式设计 */
@media (max-width: 1024px) {
  .hero .container,
  .speed .container,
  .security .container {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-visual,
  .speed-visual,
  .security-visual {
    order: -1;
  }
  
  .hero-content h1,
  .speed-content h2,
  .security-content h2 {
    font-size: var(--font-size-4xl);
  }
  
  .footer-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
  }
}

@media (max-width: 768px) {
  .navbar-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
  }
  
  .navbar-menu.active {
    display: block;
  }
  
  .nav-links {
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: flex-start;
  }
  
  .mobile-menu-btn {
    display: block;
  }
  
  .hero-content h1 {
    font-size: var(--font-size-4xl);
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: stretch;
  }
  
  .browser-grid {
    grid-template-columns: 1fr;
  }
  
  .speed-stats {
    grid-template-columns: 1fr;
  }
  
  .section-header h2 {
    font-size: var(--font-size-3xl);
  }
  
  .download-hero h1 {
    font-size: var(--font-size-4xl);
  }
}

@media (max-width: 640px) {
  .container {
    padding: 0 var(--spacing-md);
  }
  
  .hero-content h1 {
    font-size: var(--font-size-3xl);
  }
  
  .section-header h2 {
    font-size: var(--font-size-2xl);
  }
  
  .speed-meter,
  .security-shield {
    width: 250px;
    height: 250px;
  }
  
  .shield-svg {
    width: 150px;
    height: 150px;
  }
  
  .platform-grid {
    grid-template-columns: 1fr;
  }
  
  .requirements-grid {
    grid-template-columns: 1fr;
  }
  
  .faq-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-links {
    grid-template-columns: 1fr;
  }
}