docs: function (type) {
        var items = this.elm_result.children;
        var index = 0;
        for (var i = 0; i < items.length; i++) {
          if (items[i].className == 'ok') {
            items[i].className = '';
            if (type == 'up') index = i - 1;
            else index = i + 1;
            break;
          };
        };
        if (items[index]) items[index].className = 'ok';
      }