var ua = navigator.userAgent.toLowerCase();

if (ua.indexOf("msie") != -1) {
    document.write('<link rel="stylesheet" type="text/css" media="all" href="./themes/Cafedre/style/ie_style.css" />');
}
if (ua.indexOf("chrom") != -1) {
    document.write('<link rel="stylesheet" type="text/css" media="all" href="./themes/Cafedre/style/chrome_style.css" />');
}