我指的是一个视频教程，其中设计师使用 font: 0/0 a; 进行图像替换，所以我得到 0 是 font- size，另一个 0 是 line-height 但设计者跳过 a 部分只是说这是一个 hack。
那么 a 到底做了什么？
最佳答案
http://nicolasgallagher.com/another-css-image-replacement-technique/
font:0/0 a – a shorthand property that zeros out the font size and line-height. The a value acts as a very short font-family (an idea taken from the BEM implementation of this method). The CSS validator complains that using 0/0 in the shorthand font property is not valid, but every browser accepts it and this appears to be an error in the validator. Using font:0px/0 a passes validation but it displayed as font:0/0 a in the code that the validator flags as valid.
关于css - "a"在字体: 0/0 a;中代表什么，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20640976/