ie6 = 		(parseFloat(navigator.appVersion.split("MSIE")[1]) != 6) ? false : true;
ie7 = 		(parseFloat(navigator.appVersion.split("MSIE")[1]) != 7) ? false : true;
ie8 = 		(parseFloat(navigator.appVersion.split("MSIE")[1]) != 8) ? false : true;
firefox = 	(navigator.userAgent.indexOf("Firefox")==-1) ? false : true;
opera = 	(navigator.userAgent.indexOf("Opera")  ==-1) ? false : true;

function loadCSS () {
	link = document.getElementById('cssLink');
	if (ie6) link.href = 'css/flotaIE6.css';
	if (ie7) link.href = 'css/flotaIE7.css';
    if (opera) link.href = 'arsobaOpera.css';
}

loadCSS();