addCSS.js

function addCSS (css){
	if (document.createStyleSheet) { // for IE
		var sheet = document.createStyleSheet();
		sheet.cssText = css;
		return sheet;
	} else {
		var sheet = document.createElement('style');
		sheet.type = 'text/css';
		var _root = document.getElementsByTagName('head')[0] || document.documentElement;
		sheet.textContent = css;
		return _root.appendChild(sheet).sheet;
	}
}