function toggle(layer) {
  var menus = layer.parentNode.getElementsByTagName("div");
  
  for (var i = 0, mlen = menus.length; i < mlen; i++) {
	var subMenu = menus.item(i);
	if (subMenu.className == "submenu") {
	  if (layer.id != subMenu.parentNode.id) {
	    hide(subMenu);
	  } else {
	    if (subMenu.style.display == "block")
		  hide(subMenu);
		else
		  show(subMenu);
	  }
    }
  }
}


function show(element) {
  element.style.display = "block";
}

function hide(element) {
  element.style.display = "none";
}