$(function(){
	$('#nav span').click(function(){
		var $this = $(this);
		$this.parent().toggleClass('opened');
		
		if ($this.next().is(':hidden'))
			$this.next().slideDown(300);
		else
			$this.next().slideUp(300);
	});
	$('#nav > li.opened').children('ul').slideDown(300);
});