code: function() {
              var containerWidth = pgwSlideshow.plugin.find('.ps-list').width();
              var listObject = pgwSlideshow.plugin.find('.ps-list > ul');
              var listWidth = listObject.width();  
  
              var marginLeft = parseInt(listObject.css('margin-left'));
              var marginRight = parseInt(listObject.css('margin-right'));
              containerWidth -= (marginLeft + marginRight);
  
              var visibleZoneStart = Math.abs(parseInt(listObject.css('left')));
              var visibleZoneEnd = visibleZoneStart + containerWidth;
              var elementZoneStart = pgwSlideshow.plugin.find('.ps-list .ps-selected').position().left;
              var elementZoneEnd = elementZoneStart + pgwSlideshow.plugin.find('.ps-list .ps-selected').width();
  
              if ((elementZoneStart < visibleZoneStart) || (elementZoneEnd > visibleZoneEnd) || (listWidth > containerWidth && visibleZoneEnd > elementZoneEnd)) {
                  var maxPosition = -(listWidth - containerWidth);
  
                  if (-elementZoneStart < maxPosition) {
                      listObject.css('left', maxPosition);
                  } else {
                      listObject.css('left', -elementZoneStart);
                  }
              }
  
              return true;
          }
docs: Check the visibility of the selected item