if (navigator.userAgent.indexOf("Safari")!=-1) document.write('<link rel="stylesheet" media="screen" type="text/css" href="'+UrlSite+'/Site/includes/css/safari.css" />');
else if (navigator.userAgent.indexOf("Opera")!=-1) document.write('<link rel="stylesheet" media="screen" type="text/css" href="'+UrlSite+'/Site/includes/css/opera.css" />');
else if (navigator.userAgent.indexOf("MSIE 7")!=-1) document.write('<link rel="stylesheet" media="screen" type="text/css" href="'+UrlSite+'/Site/includes/css/ie7.css" />');