nth-child() 选择器可以规定其遍历或选择器相同的元素的第几个。奇数:li:nth-child(odd)li:nth-child(2n-1)偶数:li:nth-child(even)li:nth-child(2n) 转载于:https://juejin.im/post/5c88ca08f265da2d864b7b3e