system= (navigator.appVersion.indexOf("Mac")==-1)?"PC":"MAC";
browser=(navigator.appName.indexOf("Microsoft")==-1)?"NS":"IE";
if (browser=="NS" && navigator.appVersion.substring(0,1)==5) { browser="IE"; }
BrowserOnSystem=browser+"on"+system;

switch (BrowserOnSystem)
	{
	 case "IEonPC":
	 document.write("<link rel=stylesheet type='text/css'  href='styles/ie_pc.css'>");
	 break;
	 case "NSonPC":
	 document.write("<link rel=stylesheet type='text/css' href='styles/ns_pc.css'>");
	 break;
	 case "IEonMAC":
	 document.write("<link rel=stylesheet type='text/css' href='styles/ie_mac.css'>");
	 break;
	 case "NSonMAC":
	 document.write("<link rel=stylesheet type='text/css' href='styles/ns_mac.css'>");
	 break;
	 default:
	 document.write("<link rel=stylesheet type='text/css' href='styles/ie_pc.css'>");
	 break;
	}