看板

使用 HTML5、CSS3 和 JavaScript 构建一个看板项目管理面板。创建一个灵活的看板布局，支持可自定义的列（待办、进行中、已完成等）。实现卡片在列之间的拖放移动，并带有平滑动画。添加卡片创建功能，支持富文本格式、标签、截止日期和优先级。包含使用头像进行用户分配，以及按负责人筛选。实现卡片评论和活动历史。添加看板自定义功能，支持列重新排序和颜色主题。支持多个看板并可快速切换。使用 localStorage 实现数据持久化，并提供导出/导入功能。创建一个能够适应不同屏幕尺寸的响应式设计。为常见操作添加键盘快捷键。

Build a Kanban project management board using HTML5, CSS3, and JavaScript. Create a flexible board layout with customizable columns (To Do, In Progress, Done, etc.). Implement drag-and-drop card movement between columns with smooth animations. Add card creation with rich text formatting, labels, due dates, and priority levels. Include user assignment with avatars and filtering by assignee. Implement card comments and activity history. Add board customization with column reordering and color themes. Support multiple boards with quick switching. Implement data persistence using localStorage with export/import functionality. Create a responsive design that adapts to different screen sizes. Add keyboard shortcuts for common actions.