function showSubmenu(event) {
	var element = Event.element(event);
	element.up('.item').addClassName('open');
	element.up('.item').removeClassName('close');
}
function hideSubmenu(event) {
	var element = Event.element(event);
	element.up('.item').removeClassName('open');
	element.up('.item').addClassName('close');
}

// Top menu 
$$('.top-menu .item')
	.invoke('observe', 'mouseover', showSubmenu)
	.invoke('observe', 'mouseout', hideSubmenu);