<p> <span style="color:#18191C;font-family:"font-size:15px;background-color:#FFFFFF;"><strong>伪类和伪元素是前端开发中会经常使用，有感兴趣的小伙伴可以看看哈~</strong></span> </p> <p> <span style="color:#18191C;font-family:"font-size:15px;background-color:#FFFFFF;"><strong><br /> </strong></span> </p> <p> <span style="color:#18191C;font-family:"font-size:15px;background-color:#FFFFFF;"><iframe src="//player.bilibili.com/player.html?aid=530947982&bvid=BV1fu41157CV&cid=1198338411&page=1" frameborder="no" width="100%" height="500px"> </iframe></span> </p>