var Zeile, CSSFile;
CSSFile="netscape.css";
if ((navigator.appName=="Microsoft Internet Explorer")
        &&(parseInt(navigator.appVersion.charAt(0))>=4))
{
      CSSFile="http://www.enduroteam.de/ie.css";
}

if ((navigator.appName=="Netscape")
        &&(parseInt(navigator.appVersion.charAt(0))>=4))
{
CSSFile="http://www.enduroteam.de/netscape.css";
}

Zeile="<LINK REL=\"STYLESHEET\" HREF=\""+CSSFile+"\" TYPE=\"text/css\">";
 document.write(Zeile);