/*
* @package css.helpers
*/
	
css.addInit(function (){
	var features = css.features = (function (){
			var ua = navigator.userAgent.toLowerCase(),
				check = function(expression){
					return expression.test(ua);
				},
				isStrict = document.compatMode == "CSS1Compat",
				isOpera = check(/opera/),
				isChrome = check(/\bchrome\b/),
				isWebKit = check(/webkit/),
				isSafari = !isChrome && check(/safari/),
				isSafari2 = isSafari && check(/applewebkit\/4/),
				isSafari3 = isSafari && check(/version\/3/),
				isSafari4 = isSafari && check(/version\/4/),
				isIE = !isOpera && check(/msie/),
				isIE7 = isIE && check(/msie 7/),
				isIE8 = isIE && check(/msie 8/),
				isIE6 = isIE && !isIE7 && !isIE8,
				isGecko = !isWebKit && check(/gecko/),
				isGecko2 = isGecko && check(/rv:1\.8/),
				isGecko3 = isGecko && check(/rv:1\.9/),
				isBorderBox = isIE && !isStrict,
				isWindows = check(/windows|win32/),
				isMac = check(/macintosh|mac os x/),
				isAir = check(/adobeair/),
				isLinux = check(/linux/);
				
			return {
				strict: 		isStrict,
				borderBox: isBorderBox,
				
				opera: 		isOpera,
				chrome:	isChrome,
				webKit: 	isWebKit,
				safari: 		isSafari,
				gecko: 		isGecko,
				ie: 			isIE,
				
				safari2: 	isSafari2,
				safari3: 	isSafari3,
				safari4: 	isSafari4,
				ie6: 			isIE6,
				ie7: 			isIE7,
				ie8: 			isIE8,
				gecko2: 	isGecko2,
				gecko3: 	isGecko3,
				
				windows: 	isWindows,
				mac: 		isMac,
				air: 			isAir,
				linux: 		isLinux
			};
		})();
	
	css.updateFeatures = function (){
		var body = document.getElementsByTagName("body")[0],
			attribute = body.className.replace(/\bno-js\b/g, "js"),
			classes = attribute.split(" ");
	
		for (var key in features){
			var feature = features[key];
			
			if (feature){
				classes.push((feature != true && feature != false ? feature : "") + key);
			}
		}
		
		var tmp = {}, length = classes.length;
		
		for (var index = 0; index < length; index++){
			tmp[classes[index]] = true;
		}
		
		classes = [];
		for (var key in tmp){
			if (tmp[key] === true){
				classes.push(key);
			}
		}
		
		body.className = classes.join(" ");
	};
	
	css.updateFeatures();
});