var id_menu = new Array('sub_menu_1','sub_menu_2','sub_menu_3');
function allclose() {
	for (i=0; i < id_menu.length; i++){
		document.getElementById(id_menu[i]).style.display="none";
	}
}
function openMenu(id){
	if (document.getElementById(id).style.display=="block"){
		document.getElementById(id).style.display="none";
	}else{
		document.getElementById(id).style.display="block"; 
	}
}