理解僞元素 :before 和 :after

時間 2021-01-04

原文原文鏈接

層疊樣式表（CSS）的主要目的是給HTML元素添加樣式，然而，在一些案例中給文檔添加額外的元素是多餘的或是不可能的。事實上CSS中有一個特性允許我們添加額外元素而不擾亂文檔本身，這就是「僞元素」。你一定聽說過這個詞，尤其是當你一直關注着我們的教程。點此瀏覽原作者的其他文章事實上，的確有一些CSS家族的成員（CSS選擇器）被分類爲僞元素比如：:first-line, :first-letter,

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1. 對僞元素::after和::before的理解
2. 理解僞元素 :Before 和 :After
3. 理解:Before和:After僞元素
4. 理解僞元素 :before 和 :after
5. 僞元素 before after
6. 僞元素::after和::before
7. before和：after僞元素
8. ::before 和 ::after 僞元素
9. css僞元素after、before
10. css僞元素 ::after ::before
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