var current_category = '';

function openCategory(cat) {
	if(current_category != '') {
		closeCategory(current_category);
	}
	hide(cat);
	show(cat + '-on');
	show(cat + '-sub');
	
	current_category = cat;
	
	return false;
}

function closeCategory(cat) {
	hide(cat + '-on');
	hide(cat + '-sub');
	current_category = cat;
	show(cat);
	return false;
}