if ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) < 4 )) {
   document.write("<LINK REL=stylesheet HREF=\"stylesheets/ie3.css\" TYPE=\"text/css\">"); }
else if ((navigator.appName == "Microsoft Internet Explorer") && (navigator.appVersion.indexOf("Mac") != -1)) {
   document.write("<LINK REL=stylesheet HREF=\"stylesheets/mac.css\" TYPE=\"text/css\">"); }
else if ((navigator.appName == "Netscape") && (navigator.appVersion.indexOf("Mac") != -1)) {
   document.write("<LINK REL=stylesheet HREF=\"stylesheets/macnav.css\" TYPE=\"text/css\">"); }
else if ((navigator.appName == "Netscape") && (navigator.appVersion.indexOf("Mac") == -1)) {
   document.write("<LINK REL=stylesheet HREF=\"stylesheets/nav.css\" TYPE=\"text/css\">"); }
else {
   document.write("<LINK REL=stylesheet HREF=\"stylesheets/portal.css\" TYPE=\"text/css\">"); }