多级手风琴式导航菜单

尝试使用jquery创建一个类似手风琴的多级导航菜单。我从一篇帖子中得到了这个，我能够做到，但挑战是点击sub-sub-items时不会显示。

FIDDLE

HTML:

<div class="sidebar">
    <ul>
        <li>
            <a href="javascript:void(0)">Item 1</a>
            <ul class="sub-menu">
                <li>
                    <a href="javascript:void(0)">Sub Item 1</a>
                </li>
                <li>
                    <a href="javascript:void(0)">Sub Item 2</a>
                </li>
                <li>
                    <a href="javascript:void(0)">Sub Item 3</a>
                </li>
                <li>
                    <a href="javascript:void(0)">Sub Item 4</a>
                </li>
            </ul>
        </li>
        <li>
            <a href="javascript:viod(0)">Item 2</a>
            <ul class="sub-menu">
                <li>
                    <a href="javascript:void(0)">Sub Item 1</a>
                    <ul class="sub-sub-menu">
                        <li>
                            <a href="javascript:void(0)">Sub Sub Item 1</a>
                        </li>
                        <li>
                            <a href="javascript:void(0)">Sub Sub Item 2</a>
                        </li>
                        <li>
                            <a href="javascript:void(0)">Sub Sub Item 3</a>
                        </li>
                        <li>
                            <a href="javascript:void(0)">Sub Sub Item 4</a>
                        </li>
                    </ul>
                </li>
                <li>
                    <a href="javascript:void(0)">Sub Item 2</a>
                </li>
                <li>
                    <a href="javascript:void(0)">Sub Item 3</a>
                </li>
            </ul>
        </li>
        <li>
            <a href="javascript:viod(0)">Item 3</a>
        </li>
        <li>
            <a href="javascript:viod(0)">Item 4</a>
        </li>
        <li>
            <a href="javascript:viod(0)">Item 5</a>
        </li>
    </ul>  
</div>

JS:

$('.sidebar > ul > li > a').click(function(ev) {
    $('.sidebar .sub-menu, .sub-menu .sub-sub-menu').stop().slideUp();
    $(this).next('.sub-menu').stop().slideToggle();
    ev.stopPropagation();
});

请帮我把这个修好。