function Is()
{
	var agent = navigator.userAgent.toLowerCase();
	this.major = parseInt(navigator.appVersion);
	this.minor = parseFloat(navigator.appVersion);
	this.ns = ((agent.indexOf('mozilla') != -1) && ((agent.indexOf('spoofer') == -1) && (agent.indexOf('compatible') == -1)));
	this.opera = (agent.indexOf('opera') != -1);
	this.gecko = ((agent.indexOf('mozilla') != -1) && ((agent.indexOf('gecko') != -1)));
	this.ns4 = (this.ns && (this.major >= 4));
	this.ie = (agent.indexOf("msie") != -1);
	this.ie4 = (this.ie && (this.major >= 4));
	this.win = (agent.indexOf("win") != -1);
	this.mac = (agent.indexOf("mac") != -1);
}        

function CSSSwitch(root) { 
	var is = new Is();
	if (is.ie4) {
		if (is.mac)
			document.write('<link rel="stylesheet" type="text/css" href="'+root+'/lib/ie.css">');
		else
			document.write('<link rel="stylesheet" type="text/css" href="'+root+'/lib/ie.css">');
	}	else if (is.gecko) {
			document.write('<link rel="stylesheet" type="text/css" href="'+root+'/lib/gecko.css">');
	} else if (is.opera) {
			document.write('<link rel="stylesheet" type="text/css" href="'+root+'/lib/opera.css">');		
	} else if (is.ns4) {
		if (is.mac)
			document.write('<link rel="stylesheet" type="text/css" href="'+root+'/lib/ns.css">');
		else
			document.write('<link rel="stylesheet" type="text/css" href="'+root+'/lib/ns.css">');
	}
}