$ is not a function解决办法

$有问题时，采用以下方式

<code class="">(function ($) {
    $('.portfolio-two-item').click(function () {
        var video_path = $(this).data('src');
        layer.open({
          type: 2,
          title: '查看视频',
          shadeClose: true,
          shade: 0.8,
          // area: ['100%', '600px'],
          content: video_path //iframe的url &lt;iframe height=498 width=510 src='https://player.youku.com/embed/XNDE4NzExNTEzMg==' frameborder=0 'allowfullscreen'&gt;&lt;/iframe&gt;
        });
    })    
})(jQuery);
</code>