<script>setTimeout(() => {
      if (IsPC()) {
        document.getElementById('pc_mode').style.display = 'block'
      }
    }, 500);

    function IsPC() {
      var userAgentInfo = navigator.userAgent;
      var Agents = ["Android", "iPhone",
        "SymbianOS", "Windows Phone",
        "iPad", "iPod"
      ];
      var flag = true;
      for (var v = 0; v < Agents.length; v++) {
        if (userAgentInfo.indexOf(Agents[v]) > 0) {
          flag = false;
          break;
        }
      }
      return flag;
    }</script>

js 判断网页访问的效果，改变效果