s6 layui-col-md12">
      <div class="grid-demo grid-demo-bg2">移动设备：50%、桌面：100%</div>
    </div>
  </div>

  <fieldset class="layui-elem-field layui-field-title">
    <legend>移动设备、平板、桌面端的不同展现</legend>
  </fieldset>

  <div class="layui-row">
    <div class="layui-col-xs6 layui-col-sm6 layui-col-md4">
      <div class="grid-demo grid-demo-bg1">50% | 33.33% | 33.33%</div>
    </div>
    <div class="layui-col-xs6 layui-col-sm6 layui-col-md4">
      <div class="