/* 加载动画 */
    .loading-overlay {
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background: rgba(13, 13, 13, 0.9);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      z-index: 100;
    }

    .loading-spinner {
      width: 48px;
      height: 48px;
      border: 3px solid var(--border-color);
      border-top-color: var(--accent-primary);
      border-radius: 50%;
      animation: spin 1s linear infinite;
    }

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

    .loading-text {
      margin-top: 16px;
      font-size: 14px;
      color: var(--text-secondary);
    }

    /* 替换记录面板 */
    .replacement-list {
      max-height: 200px;
      overflow-y: auto;
    }

    .replacement-item {
      display: flex;
      align-items: center;
      gap: 8px;
      padding: 8px 12px;
      border-bottom: 1px solid var(--border-color);
    }

    .replacement-arrow {
      color: var(--text-muted);
      font-size: 14px;
    }

    .replacement-delete {
      width: 24px;
      height: 24px;
      border: none;
      background: transparent;
      color: var(--text-muted);
      cursor: pointer;
      border-radius: 4px;
      margin-left: auto;
    }

    .replacement-delete:hover {
      background: var(--danger);
      color: white;
    }

    /* 尺寸控制 */
    .size-control {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .size-input {
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .size-input label {
      font-size: 12px;
      color: var(--text-muted);
    }

    /* 画笔模式指示 */
    .brush-indicator {
      position: fixed;
      bottom: 100px;
      left: 50%;
      transform: translateX(-50%);
      background: rgba(0, 212, 170, 0.75);
      color: var(--bg-primary);
      padding: 12px 24px;
      border-radius: 24px;
      font-size: 14px;
      font-weight: 500;
      display: flex;
      align-items: center;
      gap: 10px;
      box-shadow: 0 4px 20px var(--accent-glow);
      z-index: 100;
      user-select: none;
      touch-action: none;
      white-space: nowrap;
      max-width: 95vw;
    }

    .brush-color {
      width: 24px;
      height: 24px;
      border-radius: 4px;
      border: 2px solid white;
    }
    
    .brush-color.empty-bead-checker {
      background-image: linear-gradient(45deg, #ccc 25%, transparent 25%),
                        linear-gradient(-45deg, #ccc 25%, transparent 25%),
                        linear-gradient(45deg, transparent 75%, #ccc 75%),
                        linear-gradient(-45deg, transparent 75%, #ccc 75%);
      background-size: 8px 8px;
      background-position: 0 0, 0 4px, 4px -4px, -4px 0;
      background-color: #fff;
    }

    /* 画笔形状按钮 */
    .brush-shape-btn {
      display: inline-flex;
      align-items: center;
      gap: 5px;
      cursor: pointer;
      padding: 2px 6px;
      border-radius: 4px;
      transition: background 0.15s;
      line-height: 1;
    }
    .brush-shape-btn:hover {
      background: rgba(255, 255, 255, 0.15);
    }

    /* 画笔形状大小选择弹窗 */
    .brush-shape-picker {
      position: fixed;
      bottom: 160px;
      left: 50%;
      transform: translateX(-50%);
      background: var(--bg-primary, #1a1a2e);
      border: 1px solid var(--border-color, rgba(255,255,255,0.12));
      border-radius: 12px;
      padding: 16px;
      z-index: 101;
      box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
      width: 260px;
      user-select: none;
    }

    .bsp-section {
      margin-bottom: 14px;
    }
    .bsp-section:last-child {
      margin-bottom: 0;
    }

    .bsp-label {
      font-size: 12px;
      font-weight: 600;
      color: var(--text-secondary, #aaa);
      margin-bottom: 8px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .bsp-options {
      display: flex;
      gap: 8px;
    }

    .bsp-option {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      padding: 8px 14px;
      border-radius: 8px;
      cursor: pointer;
      background: var(--bg-secondary, rgba(255,255,255,0.06));
      border: 2px solid transparent;
      color: var(--text-primary, #eee);
      transition: all 0.15s;
      flex: 1;
    }
    .bsp-option:hover {
      background: var(--bg-hover, rgba(255,255,255,0.1));
    }
    .bsp-option.active {
      border-color: var(--accent-color, #00d4aa);
      background: rgba(0, 212, 170, 0.12);
      color: var(--accent-color, #00d4aa);
    }
    .bsp-option span {
      font-size: 11px;
      font-weight: 500;
    }

    /* 画笔大小滑动条 */
    .bsp-slider-row {
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .bsp-slider-label {
      font-size: 12px;
      color: var(--text-secondary, #aaa);
      min-width: 16px;
      text-align: center;
      font-weight: 500;
    }

    .bsp-slider {
      flex: 1;
      -webkit-appearance: none;
      appearance: none;
      height: 6px;
      border-radius: 3px;
      background: var(--bg-secondary, rgba(255,255,255,0.12));
      outline: none;
      cursor: pointer;
    }
    .bsp-slider::-webkit-slider-thumb {
      -webkit-appearance: none;
      appearance: none;
      width: 18px;
      height: 18px;
      border-radius: 50%;
      background: var(--accent-color, #00d4aa);
      cursor: pointer;
      box-shadow: 0 1px 4px rgba(0,0,0,0.3);
      transition: transform 0.1s;
    }
    .bsp-slider::-webkit-slider-thumb:hover {
      transform: scale(1.15);
    }
    .bsp-slider::-moz-range-thumb {
      width: 18px;
      height: 18px;
      border-radius: 50%;
      background: var(--accent-color, #00d4aa);
      cursor: pointer;
      border: none;
      box-shadow: 0 1px 4px rgba(0,0,0,0.3);
    }
    .bsp-slider::-moz-range-track {
      height: 6px;
      border-radius: 3px;
      background: var(--bg-secondary, rgba(255,255,255,0.12));
    }

    /* 画笔预览网格 */
    .bsp-preview {
      margin-top: 14px;
      padding-top: 14px;
      border-top: 1px solid var(--border-color, rgba(255,255,255,0.1));
    }

    .bsp-preview-label {
      font-size: 12px;
      font-weight: 600;
      color: var(--text-secondary, #aaa);
      margin-bottom: 8px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .bsp-preview-grid {
      display: grid;
      grid-template-columns: repeat(12, 1fr);
      gap: 2px;
      width: 192px;
      margin: 0 auto;
    }

    .bsp-preview-cell {
      aspect-ratio: 1;
      border-radius: 2px;
      background: var(--bg-secondary, rgba(255,255,255,0.06));
      transition: background 0.1s;
    }
    .bsp-preview-cell.filled {
      background: var(--accent-color, #00d4aa);
    }

    .bsp-confirm-btn {
      display: block;
      width: 100%;
      margin-top: 14px;
      padding: 8px 0;
      border: none;
      border-radius: 8px;
      background: var(--accent-color, #00d4aa);
      color: var(--bg-primary, #1a1a2e);
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      transition: opacity 0.15s;
    }
    .bsp-confirm-btn:hover {
      opacity: 0.85;
    }

    /* 画笔光标预览（桌面端悬停显示覆盖区域） */
    .brush-cursor-preview {
      position: fixed;
      pointer-events: none;
      border: 1.5px solid rgba(255, 255, 255, 0.85);
      box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.5);
      z-index: 1000;
      will-change: left, top;
    }

    /* 移动端画笔形状弹窗调整 */
    @media (max-width: 768px) {
      .brush-shape-picker {
        bottom: 140px;
        width: 250px;
        padding: 14px;
      }
      .bsp-option {
        padding: 6px 10px;
      }
      .bsp-preview-grid {
        width: 180px;
      }
    }

    /* 响应式 */
    @media (max-width: 1400px) {
      .left-panel {
        width: 280px;
      }
    }

    @media (max-width: 1200px) {
      .right-panel {
        width: 250px;
      }
      .left-panel {
        width: 260px;
      }
    }

    @media (max-width: 992px) {
      .main-content {
        flex-direction: column;
        overflow: auto;
      }

      .left-panel,
      .right-panel {
        width: 100%;
        max-height: none;
        flex-shrink: 0;
      }

      .center-panel {
        min-height: 50vh;
        flex-shrink: 0;
      }

      .steps-nav {
        display: none;
      }
      
      .header-actions .btn {
        padding: 6px 12px;
        font-size: 12px;
      }
      
      .info-content {
        gap: 16px;
      }
      
      .info-item {
        font-size: 11px;
      }
    }