描述一个记忆翻牌游戏：翻转动画、不同难度网格、计时与步数、音效和排行榜。
使用 HTML5、CSS3 和 JavaScript 开发一款记忆匹配卡片游戏。创建视觉上吸引人的卡片设计，并配备翻转动画。实现多个难度等级，对应不同的网格尺寸和卡片数量。添加计时器与步数计数器以支持计分。为卡片翻转与成功匹配添加音效。实现排行榜功能，并持久化存储分数。添加主题选择功能，支持不同风格的卡片设计。包含多人游戏模式，支持竞技性对战。创建响应式布局，可随屏幕尺寸自适应调整。添加无障碍功能，支持键盘导航。在游戏过程中实现渐进式难度提升。
Develop a memory matching card game using HTML5, CSS3, and JavaScript. Create visually appealing card designs with flip animations. Implement difficulty levels with varying grid sizes and card counts. Add timer and move counter for scoring. Include sound effects for card flips and matches. Implement leaderboard with score persistence. Add theme selection with different card designs. Include multiplayer mode for competitive play. Create responsive layout that adapts to screen size. Add accessibility features for keyboard navigation. Implement progressive difficulty increase during gameplay.