/**
 * Chunk Virtual Rendering - 分块虚拟化渲染优化
 *
 * 职责：分块对比虚拟化性能优化
 * 作用域：.chunk-compare-container 及虚拟化相关元素
 * 依赖：variables.css
 *
 * 提取自：chunk_compare_optimizer.css
 *
 * 包含：
 * - 虚拟化占位符样式
 * - 骨架屏加载动画
 * - 分块优化渲染
 * - 性能模式样式
 * - 加载状态与错误处理
 */

/* ==================== 1. 虚拟化容器 ==================== */

/* 优化后的分块容器 */
.chunk-compare-container {
  position: relative;
  /* 取消内部滚动与固定高度，改由页面整体滚动 */
  /* overflow-y: auto; */
  /* max-height: 80vh; */
  scroll-behavior: smooth;
  margin: 0;
  padding: 0;
}

/* 移除虚拟化占位符的多余空间 */
.virtual-spacer-top,
.virtual-spacer-bottom {
  margin: 0;
  padding: 0;
  line-height: 0;
  font-size: 0;
  background: transparent;
  pointer-events: none;
}

/* ==================== 2. 骨架屏样式 ==================== */

.skeleton-chunk {
  margin-bottom: var(--spacing-md);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  background: var(--color-bg-primary);
}

.skeleton-line {
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--radius-sm);
  height: 12px;
  margin-bottom: var(--spacing-sm);
}

.skeleton-title {
  height: 16px;
  width: 30%;
}

.skeleton-label {
  height: 10px;
  width: 20%;
  margin-bottom: 6px;
}

.skeleton-stat {
  height: 10px;
  width: 60px;
  display: inline-block;
  margin-right: var(--spacing-sm);
}

.skeleton-short {
  width: 60%;
}

.skeleton-content {
  margin-bottom: var(--spacing-sm);
}

.skeleton-button {
  height: 32px;
  width: 120px;
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: 6px;
  margin: 0 auto;
}

.skeleton-stats {
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
}

@keyframes skeleton-loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

/* ==================== 3. 分块预览样式 ==================== */

.chunk-preview-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
}

.chunk-compare-title-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1em;
  padding: 0.5em 0;
  border-bottom: 1px solid var(--color-border-light);
}

.chunk-controls {
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
}

.chunk-count {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  font-weight: normal;
}

.performance-btn {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-sm);
  padding: 4px 8px;
  cursor: pointer;
  font-size: 1.2em;
  transition: all var(--transition-fast);
}

.performance-btn:hover {
  background: #e0e7ff;
  border-color: var(--color-primary);
}

.performance-btn.active {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

/* ==================== 4. 优化分块样式 ==================== */

.optimized-chunk {
  margin-bottom: 1.5em;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: box-shadow var(--transition-fast);
  background: var(--color-bg-primary);
}

.optimized-chunk:hover {
  box-shadow: var(--shadow-md);
}

.chunk-header {
  background: var(--color-bg-secondary);
  border-bottom: 1px solid var(--color-border-light);
  padding: var(--spacing-sm) var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chunk-header h4 {
  margin: 0;
  font-size: 1.1em;
  color: var(--color-text-primary);
}

.chunk-stats {
  display: flex;
  gap: var(--spacing-sm);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.chunk-preview-container {
  padding: var(--spacing-md);
}

.chunk-preview {
  margin-bottom: var(--spacing-sm);
  border: 1px dashed var(--color-border-light);
  border-radius: var(--radius-sm);
  padding: var(--spacing-sm);
  background: #fafbfc;
}

.preview-label {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  font-weight: var(--font-weight-semibold);
  margin-bottom: 4px;
}

.preview-content {
  font-size: var(--font-size-sm);
  line-height: var(--leading-normal);
  color: var(--color-text-secondary);
  max-height: 60px;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ==================== 5. 加载完整内容按钮 ==================== */

.load-full-content-btn {
  background: linear-gradient(135deg, var(--color-primary), #1e40af);
  color: white;
  border: none;
  border-radius: 6px;
  padding: 10px 16px;
  cursor: pointer;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  text-align: center;
  transition: all var(--transition-base);
  margin-top: var(--spacing-sm);
  box-shadow: 0 2px 4px rgba(59, 130, 246, 0.2);
}

.load-full-content-btn:hover {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  transform: translateY(-1px);
  box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
}

.load-full-content-btn:active {
  transform: translateY(0);
}

.load-full-content-btn:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* ==================== 6. 加载状态样式 ==================== */

.chunk-loading {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-lg);
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.chunk-loading::before {
  content: '';
  width: 20px;
  height: 20px;
  border: 2px solid var(--color-border-light);
  border-top: 2px solid var(--color-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-right: var(--spacing-sm);
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.chunk-loading-indicator {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: rgba(255, 255, 255, 0.95);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg) 30px;
  box-shadow: var(--shadow-lg);
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.loading-spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--color-border-light);
  border-top: 2px solid var(--color-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

/* ==================== 7. 错误状态样式 ==================== */

.chunk-error {
  padding: var(--spacing-md);
  background: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: 6px;
  color: #dc2626;
  text-align: center;
  font-size: var(--font-size-sm);
}

/* ==================== 8. 性能模式样式 ==================== */

.performance-mode .chunk-preview {
  background: #f0f9ff;
  border-color: #bae6fd;
}

.performance-mode .optimized-chunk {
  border-left: 3px solid var(--color-primary);
}

/* ==================== 9. 进度条样式 ==================== */

.chunk-progress-container {
  margin: var(--spacing-sm) 0;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  overflow: hidden;
  height: 4px;
}

.chunk-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), #06b6d4);
  transition: width var(--transition-base);
  border-radius: var(--radius-sm);
}

/* ==================== 10. 滚动条优化 ==================== */

.chunk-compare-container::-webkit-scrollbar {
  width: 8px;
}

.chunk-compare-container::-webkit-scrollbar-track {
  background: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
}

.chunk-compare-container::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: var(--radius-sm);
  transition: background var(--transition-fast);
}

.chunk-compare-container::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-secondary);
}

/* ==================== 11. 响应式优化 ==================== */

@media (max-width: 768px) {
  .chunk-header {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-sm);
  }

  .chunk-stats {
    flex-direction: column;
    gap: 4px;
  }

  .chunk-preview-container {
    padding: var(--spacing-sm);
  }

  .load-full-content-btn {
    padding: 8px 12px;
    font-size: var(--font-size-xs);
  }
}

/* ==================== 12. 高对比度模式 ==================== */

@media (prefers-contrast: high) {
  .optimized-chunk {
    border: 2px solid #000;
  }

  .chunk-header {
    background: #f0f0f0;
    border-bottom: 2px solid #000;
  }

  .load-full-content-btn {
    background: #000;
    border: 2px solid #000;
  }
}

/* ==================== 13. 减少动画偏好 ==================== */

@media (prefers-reduced-motion: reduce) {
  .optimized-chunk,
  .load-full-content-btn,
  .performance-btn {
    transition: none;
  }

  .loading-spinner {
    animation: none;
  }

  .chunk-loading::before {
    animation: none;
  }
}

/* ==================== 14. 深色模式支持 ==================== */

@media (prefers-color-scheme: dark) {
  .optimized-chunk {
    background: #1e293b;
    border-color: #475569;
  }

  .chunk-header {
    background: #334155;
    border-bottom-color: #475569;
  }

  .chunk-header h4 {
    color: #f1f5f9;
  }

  .chunk-stats {
    color: #94a3b8;
  }

  .chunk-preview {
    background: #0f172a;
    border-color: #475569;
  }

  .preview-label {
    color: #cbd5e1;
  }

  .preview-content {
    color: #94a3b8;
  }

  .chunk-loading-indicator {
    background: rgba(30, 41, 59, 0.95);
    border-color: #475569;
    color: #cbd5e1;
  }
}

/* ==================== 15. 打印样式 ==================== */

@media print {
  .chunk-controls,
  .load-full-content-btn,
  .chunk-loading-indicator {
    display: none !important;
  }

  .optimized-chunk {
    border: 1px solid #000;
    break-inside: avoid;
    margin-bottom: 1em;
  }

  .chunk-preview-container {
    padding: var(--spacing-sm);
  }
}