function getElementsByClassName(class_name){
	var all_obj,ret_obj=new Array(),j=0,teststr;
	if(document.all){
		all_obj=document.all;
	}else if(document.getElementsByTagName && !document.all){
		all_obj=document.getElementsByTagName("*");
	}
	for(i=0;i<all_obj.length;i++){
		if(all_obj[i].className.indexOf(class_name)!=-1){
			teststr=","+all_obj[i].className.split(" ").join(",")+",";
			if(teststr.indexOf(","+class_name+",")!=-1){
				ret_obj[j]=all_obj[i];
				j++;
			}
		}
	}
	return ret_obj;
}

var actNav = "";

function showNav(what, target){
	if($(what)){
		/* offene ausblenden */
		if(what == '' || $(what).className == 'first'){
			var items = getElementsByClassName('first');
			for (var i = 0; i < items.length; i++){
				items[i].style.display = "none";
			}
		}
		if(what == actNav){
			/* ausblenden */
			$(what).style.display = "none";
			actNav = "";
			return false;
		}else{
			/* einblenden */
			new Effect.Appear(what);
			actNav = what;
			return false;
		}
	}else{
		document.location = target;
	}
}

function sizeBg(){
	if($('bgimg')){
		new Effect.Appear(
			'bgimg'
		);
	}
}