function $(obj) {
	return typeof obj == 'string' ? document.getElementById(obj) : obj;
}

function addEvent(oTar , eType , funcHandler) {
	 if (oTar.addEventListener) {
        oTar.addEventListener(eType, funcHandler, false);
    } else if (oTar.attachEvent) {
        oTar.attachEvent("on" + eType, funcHandler);
    } else {
        oTar["on" + eType] = funcHandler;
    }
}

function globalInit(){
	oCon = $('gm_image_class');
	aDt = oCon.getElementsByTagName('dt');
	oNavCon = $('nav2');
	aLi = oNavCon.getElementsByTagName('Li');	
}

function menu() {
	var oCon = $('gm_image_class');
	var aDt = oCon.getElementsByTagName('dt');
	for (var i = 0,iLen = aDt.length ; i < iLen ; i++ ){
		aDt[i].local = i;
		addEvent(aDt[i],'click',function(){
			var e = window.event || arguments[0];
			var oTar = e.srcElement || e.target;
			oTar = oTar.nodeName == 'SPAN'?oTar.parentNode:oTar;
			if(oTar.parentNode.className == 's'){
				oTar.parentNode.className = '';
				aLi[oTar.local].className = '';
			}else{
				clearStyle();
				oTar.parentNode.className = 's';
				aLi[oTar.local].className = 'select';
			}
		});
	}
}

function navInit() {
	var oNavCon = $('nav2');
	var aLi = oNavCon.getElementsByTagName('Li');	
	for (var j = 0,aLen = aLi.length ; j < aLen ; j++ ){
		aLi[j].local = j;
		addEvent(aLi[j],'click',function(){
			var e = window.event || arguments[0];
			var oTar = e.srcElement || e.target;
			clearStyle();			
			aDt[oTar.local].parentNode.className = 's';
			oTar.className = 'select';
		});
	}
}

function clearStyle(){
	for (var i = 0,iLen = aDt.length ; i < iLen ; i++)
		aDt[i].parentNode.className = '';
	for (var j = 0,aLen = aLi.length ; j < aLen ; j++ )
		aLi[j].className = '';
}

addEvent(window,'load',globalInit);
addEvent(window,'load',menu);
addEvent(window,'load',navInit)