// JavaScript Document

function roll(option){
	var parent = option.parentNode;
	var parent_name = parent.getAttribute("id");
	
	if(parent_name != "menu_item_pos"){
		option.parentNode.setAttribute("id","menu_item_over");
	}
}

function unroll(option){
	var parent = option.parentNode;
	var parent_name = parent.getAttribute("id");
	
	if(parent_name == "menu_item_over"){
		option.parentNode.setAttribute("id","menu_item");
	}	
}