问题：@click事件绑定在1和2的父级盒子上，但是点击2盒子有效，点击1盒子无效

代码：

  <div class="itemlist">
      <div class="item" @click="toSecurity()">
        <div class="bg bg_aq">
          <div class="iconfont icon-anquan icon2"></div>
        </div>
        <div class="text">安全常识</div>
      </div>

      <div class="item" @click="toLaw">
        <div class="bg bg_fv">
          <div class="iconfont icon-falv icon2"></div>
        </div>

        <div class="text">法律法规</div>
      </div>
      <div class="item" @click="toEducation">
        <div class="bg bg_peixun">
          <div class="iconfont icon-peixun icon2"></div>
        </div>

        <div class="text">教育培训</div>
      </div>
      <div class="item" @click="toMeeting">
        <div class="bg bg_shipin">
          <div class="iconfont icon-shizhengxiaohuoshuan icon2"></div>
        </div>
        <div class="text">视频会议</div>
      </div>
    </div>

原因：<div class="bg bg_aq"> <div class="iconfont icon-anquan icon2"></div> </div> 的z-index太小了

解决：修改.bg的css样式