# 伪类与伪元素

## 伪类

![](/files/-LviSIQMm1nBcyiLXvHs)

## 伪元素

![](/files/-LviTO9q_n5u8GOGjjxG)

## 区别

1. 伪元素在一个选择器里只能出现一次，并且只能出现在末尾;
2. 伪类则是像真正的类一样发挥着类的作用，没有数量上的限制，只要不是相互排斥的伪类，也可以同时使用在相同的元素上。


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