Frontend =
{
    ajaxBlock : function (id, el)
    {
        block = $('#block-' + id);

        block.fadeTo(200, 0.7);

        $.ajax({
            url : el.href,
            data : 'ajax=1&id_block=' + id,
            type : 'GET',
            dataType : 'html',
            success : function ( html ) {
                $('#block-' + id).replaceWith(html);
            },
            complete : function () {
                block.fadeTo(0, 1);
            }
        });
    }
}