Bootstrap灯箱，下一个箭头未对齐

Question

对于我正在开发的其中一个网站，我使用了引导灯箱，以及下一个和后一个按钮。因此，当单击视频或图像时，从滑块中它将显示在灯箱中，然后下一个按钮将有助于导航。在导航箭头时，假设在中间突然移动到顶部。怎么能阻止它移动？

灯箱的java脚本代码

EkkoLightbox.prototype = {
    modal_shown: function() {
      var video_id,
        _this = this;
      if (!this.options.remote) {
        return this.error('No remote target given');
      } else {
        this.gallery = this.$element.data('gallery');
        if (this.gallery) {
          if (this.options.gallery_parent_selector === 'document.body' || this.options.gallery_parent_selector === '') {
            this.gallery_items = $(document.body).find('*[data-toggle="lightbox"][data-gallery="' + this.gallery + '"]');
          } else {
            this.gallery_items = this.$element.parents(this.options.gallery_parent_selector).first().find('*[data-toggle="lightbox"][data-gallery="' + this.gallery + '"]');
          }
          this.gallery_index = this.gallery_items.index(this.$element);
          $(document).on('keydown.ekkoLightbox', this.navigate.bind(this));
          if (this.options.directional_arrows && this.gallery_items.length > 1) {
            this.lightbox_container.append('<div class="ekko-lightbox-nav-overlay"><a href="#" class="' + this.strip_stops(this.options.left_arrow_class) + '"></a><a href="#" class="' + this.strip_stops(this.options.right_arrow_class) + '"></a></div>');
            this.modal_arrows = this.lightbox_container.find('div.ekko-lightbox-nav-overlay').first();
            this.lightbox_container.find('a' + this.strip_spaces(this.options.left_arrow_class)).on('click', function(event) {
              event.preventDefault();
              return _this.navigate_left();
            });
            this.lightbox_container.find('a' + this.strip_spaces(this.options.right_arrow_class)).on('click', function(event) {
              event.preventDefault();
              return _this.navigate_right();
            });
          }
        }
        if (this.options.type) {
          if (this.options.type === 'image') {
            return this.preloadImage(this.options.remote, true);
          } else if (this.options.type === 'youtube' && (video_id = this.getYoutubeId(this.options.remote))) {
            return this.showYoutubeVideo(video_id);
          } else if (this.options.type === 'vimeo') {
            return this.showVimeoVideo(this.options.remote);
          } else if (this.options.type === 'instagram') {
            return this.showInstagramVideo(this.options.remote);
          } else if (this.options.type === 'url') {
            return this.loadRemoteContent(this.options.remote);
          } else if (this.options.type === 'video') {
            return this.showVideoIframe(this.options.remote);
          } else {
            return this.error("Could not detect remote target type. Force the type using data-type=\"image|youtube|vimeo|instagram|url|video\"");
          }
        } else {
          return this.detectRemoteType(this.options.remote);
        }
      }
    },
    strip_stops: function(str) {
      return str.replace(/\./g, '');
    },
    strip_spaces: function(str) {
      return str.replace(/\s/g, '');
    },
    isImage: function(str) {
      return str.match(/(^data:image\/.*,)|(\.(jp(e|g|eg)|gif|png|bmp|webp|svg)((\?|#).*)?$)/i);
    },
    isSwf: function(str) {
      return str.match(/\.(swf)((\?|#).*)?$/i);
    },
    getYoutubeId: function(str) {
      var match;
      match = str.match(/^.*(youtu.be\/|v\/|u\/\w\/|embed\/|watch\?v=|\&v=)([^#\&\?]*).*/);
      if (match && match[2].length === 11) {
        return match[2];
      } else {
        return false;
      }
    },
    getVimeoId: function(str) {
      if (str.indexOf('vimeo') > 0) {
        return str;
      } else {
        return false;
      }
    },
    getInstagramId: function(str) {
      if (str.indexOf('instagram') > 0) {
        return str;
      } else {
        return false;
      }
    },