理解伪元素 :Before 和 :After

时间 2021-01-04

原文原文链接

层叠样式表（CSS）的主要目的是给HTML元素添加样式，然而，在一些案例中给文档添加额外的元素是多余的或是不可能的。事实上CSS中有一个特性允许我们添加额外元素而不扰乱文档本身，这就是“伪元素”。　　你一定听说过这个词，尤其是当你一直关注着我们的教程。点此浏览原作者的其他文章　　事实上，的确有一些CSS家族的成员（CSS选择器）被分类为伪元素比如：:first-line, :first-let

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1. 对伪元素::after和::before的理解
2. 理解伪元素 :before 和 :after
3. 理解伪元素 :Before 和 :After
4. 理解:Before和:After伪元素
5. 伪元素 before after
6. 伪元素::after和::before
7. before和：after伪元素
8. ::before 和 ::after 伪元素
9. css伪元素after、before
10. css伪元素 ::after ::before
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