Get Pseudo-Element Properties with JavaScript see http://davidwalsh.name/pseudo-element js-fiddle: http://jsfiddle.net/kazu69/a6C39/

index.html

<div id="box">aaaaaaa</div>

sample.js

var color = window.getComputedStyle(document.querySelector("#box", ':before')).getPropertyValue('color');

console.log(color);

style.css

#box:before {
	content: 'BEFORE';
	color: rgb(255, 0, 0);
}