var call = "<LINK REL=STYLESHEET TYPE='text/css' HREF='include/navi.css'>";

if (navigator.appVersion.indexOf('Win') != -1)
{
   if ((navigator.appName.indexOf('Netscape') != -1) && (navigator.appVersion.indexOf('5.') == -1))
   {
      call = "<LINK REL=STYLESHEET TYPE='text/css' HREF='include/navi_netscape.css'>";
   }
}

if (navigator.appVersion.indexOf('Linux') != -1)
{
    call = "<LINK REL=STYLESHEET TYPE='text/css' HREF='include/navi_linux.css'>";
}

document.write(call.toString());