jQuery(function(){
    $('#categories a').click(function(evt){
        $('#categories a').removeClass('selected');
        $(this).addClass('selected');
        
        $('.category:visible').slideToggle();
        var hash=this.href.split(/#/)[1];
        $('#cat_'+hash).slideToggle(function(){
            window.location.hash=hash;
        });
        evt.preventDefault();
    });

    $('.category').hide();
    var current = window.location.hash.substr(1);
        current = (current ? current : $('#categories a:first').length && $('#categories a:first')[0].href.split(/#/)[1]);

    $('a[href="#'+current+'"]').addClass('selected');
    $('#cat_'+current).show();
    window.scrollTo(0,0);
});