replace = function() {
			var args = arguments, index = 0, string = args[0];
			while (++index in args) {
				string = string.replace(args[index], args[++index]);
			}
			return string;
		}
gets a mediaquery and returns a boolean or gets a css length and returns a number
@param css mediaqueries or css length
@returns {boolean|number}

based on: https://gist.github.com/jonathantneal/db4f77009b155f083738