$(document).ready(function() {
        var items = $("#menu ul li.section-title").siblings();

        // on load hide all, then show active
        items.hide();
        $(this).find("#menu ul li.active").siblings().siblings().show();

        // add pointer to title, on click hide all, show clicked menu-items if they were hidden before
        $("#menu ul li.section-title").css({cursor:"pointer"}).click(function() {
                var viewable = $(this).next().css("display");
                items.hide();
                if (viewable == 'none')
                    $(this).siblings().show();
            });
    });