if(json.facility.photos.length) {                
              for(var j = 0; j<= json.facility.photos.length; ++j) {
                if(json.facility.photos[j]) {
                  popUp += '<div class="popup-slider" style="background:url('+json.facility.photos[j].thumbnail+') center center no-repeat; background-size: cover;"></div>';
                }