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CSS

Posted by Benjamin Hedgepeth
Benjamin Hedgepeth
5,672 Points

Clearfix hack breakdown

Upon breaking down this code for the clearfix why do the before and after psuedo elements only have one colon and not two colons?

CSS

.cf:before,
.cf:after {
    content: " "; 
    display: table; 
}

.cf:after {
    clear: both;
}

1 Answer

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Supposedly single colons are for pseudo-classes, double colons are for pseudo-elements. So your question is a good one. Here is what CSS Tricks has to say:

"Every browser that supports the double colon (::) CSS3 syntax also supports just the (:) syntax, but IE 8 only supports the single-colon, so for now, it's recommended to just use the single-colon for best browser support.

":: is the newer format indented to distinguish pseudo content from pseudo selectors. If you don't need IE 8 support, feel free to use the double-colon."