var n = navigator;
// string comparisons are much easier if we lowercase everything now.
// to make indexOf() tests more compact/readable, we prepend a space 
// to the userAgent string (to get around '-1' indexOf() comparison)
var ua = ' ' + n.userAgent.toLowerCase();
var pl = n.platform.toLowerCase(); // not supported in NS3.0
var an = n.appName.toLowerCase();

// browser version
var version = n.appVersion;

var is_nn = ua.indexOf('mozilla') > 0;

// 'compatible' versions of "mozilla" aren't navigator
if(ua.indexOf('compatible') > 0) {
	is_nn = false;
}



var is_major = parseInt( version );
var is_minor = parseFloat( version );

// platform
var is_mac = ua.indexOf('mac') > 0;




if	//the browser is netscape
	((is_nn) &&
	//and the version is below 6
	(is_major < 5 ) &&
	//and the OS is Mac
	(is_mac)) 
	{
	document.write("<LINK REL=stylesheet HREF=\"http://www.bc.edu/research/nbetpp/scripts/nb_netmac.css\" TYPE=\"text/css\">")
	}
	//link to the tasc_netmac.css stylesheet


else  {
	document.write("<LINK REL=stylesheet HREF=\"http://www.bc.edu/research/nbetpp/scripts/nbetpp.css\" TYPE=\"text/css\">") 
	}