var agt=navigator.userAgent.toLowerCase();
    var is_major = parseInt(navigator.appVersion);
    var is_minor = parseFloat(navigator.appVersion);

    var is_ie     = ((agt.indexOf("msie") != -1) && (agt.indexOf("opera") == -1));

    var is_ie3    = (is_ie && (is_major < 4));

    var is_ie4    = (is_ie && (is_major == 4) && (agt.indexOf("msie 4")!=-1) );

    var is_ie5up  = (is_ie && !is_ie3 && !is_ie4);
  
   if (is_ie5up) {
 document.write('<LINK HREF="/lib/babyshowerstuff/sidenav-ie.css" TYPE="text/css" REL="stylesheet">');
    } else {
 document.write('<LINK HREF="/lib/babyshowerstuff/sidenav-ff.css" TYPE="text/css" REL="stylesheet">');
    }