function doClick_down(o){
	o.className="cs";
	var j;
	var id;
	var e;
	for(var i=1;i<=3;i++){
		id ="down"+i;
		j = document.getElementById(id);
		e = document.getElementById("nava"+i);
		if(id != o.id){
			j.className="hdp1";
			e.style.display = "none";
		}else{
			e.style.display = "block";
		}
	}
}