/* 性能优化样式 */

/* 1. 关键CSS内联 - 首屏关键样式 */
:root {
  --primary: #4A90E2;
  --secondary: #FFC107;
  --success: #28a745;
  --warning: #ffc107;
  --danger: #dc3545;
  --info: #17a2b8;
  --light: #f8f9fa;
  --dark: #343a40;
  --text-primary: #2d3748;
  --text-secondary: #718096;
  --border-color: #e2e8f0;
  --bg-light: #f7fafc;
  --bg-white: #ffffff;
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
}

/* 2. 字体显示优化 */
body {
  font-display: swap;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 3. 图片优化 */
img {
  max-width: 100%;
  height: auto;
  loading: lazy;
}

/* 4. 动画性能优化 */
.animate-in {
  will-change: transform, opacity;
  transform: translateZ(0);
  backface-visibility: hidden;
  perspective: 1000px;
}

/* 5. 滚动性能优化 */
.scroll-container {
  -webkit-overflow-scrolling: touch;
  scroll-behavior: smooth;
}

/* 6. 响应式图片 */
.responsive-img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* 7. 内容可见性优化 */
.content-visibility {
  content-visibility: auto;
  contain-intrinsic-size: auto 200px;
}

/* 8. 减少重绘和重排 */
.card, .btn, .tag, .dropdown-menu {
  transform: translateZ(0);
  will-change: transform;
}

/* 9. CSS Containment */
.section, .card, .sidebar-section {
  contain: layout style;
}

/* 10. 硬件加速 */
.hot-level-fill, .hot-level-bar {
  transform: translateZ(0);
  will-change: transform;
}

/* 11. 减少复合层 */
.dropdown-menu {
  will-change: transform, opacity;
  transform: translateZ(0);
}

/* 12. 优化选择器性能 */
.nav-link:hover,
.btn:hover,
.card:hover {
  transition: all 0.2s ease;
}

/* 13. 避免昂贵的CSS属性 */
.stat-card {
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.stat-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

/* 14. 优化字体加载 */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');
}

/* 15. 优化移动端性能 */
@media (max-width: 768px) {
  .container {
    padding-left: 1rem;
    padding-right: 1rem;
  }
  
  .nav-menu {
    transform: translateZ(0);
    will-change: transform;
  }
  
  .dropdown-menu {
    max-height: 50vh;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }
}

/* 16. 优化动画性能 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translate3d(0, 30px, 0);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideInUp {
  from {
    opacity: 0;
    transform: translate3d(0, 100%, 0);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }
}

/* 17. 优化加载状态 */
.loading {
  position: relative;
  overflow: hidden;
}

.loading::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  animation: loading 1.5s infinite;
}

@keyframes loading {
  0% { left: -100%; }
  100% { left: 100%; }
}

/* 18. 优化交互响应 */
.btn,
.nav-link,
.dropdown-item,
.card {
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

/* 19. 优化滚动条 */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

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

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

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

/* 20. 优化打印样式 */
@media print {
  .nav,
  .footer,
  .btn,
  .dropdown,
  .view-toggle {
    display: none !important;
  }
  
  body {
    font-size: 12pt;
    line-height: 1.5;
  }
  
  .container {
    max-width: 100%;
    padding: 0;
  }
}