理解:Before和:After伪元素

时间 2019-12-14

标签理解元素繁體版

原文原文链接

CSS样式表的主要做用是修饰Web页面上的HTML标记，但有时候，为了实现某个效果而往页面里反复添加某个HTML标记很繁琐，或者是显得多余，或者是因为某种缘由而作不到。这就是CSS伪元素(Pseudo-Element)能够发挥做用的地方，所谓‘伪元素’，就是自己不存在的页面元素，HTML代码里并无这样的元素，但在页面显示时，你却能看到这些原本不存在的元素发挥着做用。css 观看演示以前咱们曾简要

>>阅读原文<<

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. 伪元素 before after
5. 伪元素::after和::before
6. before和：after伪元素
7. ::before 和 ::after 伪元素
8. 伪类元素before&after
9. CSS伪类元素：after ：before
10. css伪元素 ::after ::before
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