st
        if (!topnavList.classList.contains("hidden") && !e.target.closest("#topnavList")) {
          topButton.click();
        }
      });

      // set active <a> element
      var url = window
        .location
        .href
        .toLowerCase();
      var aTags = topnavList.getElementsByTagName('a');
      for (var i = 0; i < aTags.length; i++) {
        var lowerhref = aTags[i]
          .href
          .toLowerCase();
        if (url.startsWith(lowerhref)) {
          aTags[i]
            .class