Click-through gallery with light-box

Hi,

this is my website fidastav.konekto.net and I have problem with Fotogaleria site so I created test page

https://monika.konekto.net/gallery.html

I want to make click-through gallery with light-box. Click-through gallery works perfectly but i have big problem with light-box. I do not know harmonize it. In HTML – gallery thumbnail images I put first after than I put light-box section with images.

There is jquery:

/**
 *GALLERY
 */

$(function(){

// najdeme v?etky galérie

var galleries = $('.gallery-set');

//skryjeme galérie

galleries.hide();

var selected = $('.controls').find('.selected');

//funckia na zobrazenie selektnutej galerie
function showGallery (selected) {
      if(selected.length) {
      var id = selected.find('a').attr('href');
      selectedGallery = $(id);
      }

      var newGallery = selectedGallery.length ? selectedGallery : galleries.eq(0).show();

      galleries.not( newGallery ).hide();

      newGallery.fadeIn();

       }

showGallery( selected );

$('.controls a').on('click', function() {
      var li = $(this).parent();

      li.addClass('selected').
      siblings().removeClass('selected'); 

showGallery( li );
event.preventDefault();
});

});

/**
 * SLIDER
 */

$(function () {
    var currentIndex = 0,
        lightboxLis = $('.light-box li');

var overlay = $('<div/>', {id: 'overlay'});
overlay.appendTo('body').hide();

    $('.thumbnail li').click(function () {
overlay.show();
        currentIndex = $(this).index();

        lightboxLis.eq(currentIndex).show();

        //put next prev show here otherwise it won't work due to your hover
        //when you hover the next prev button in your old version you no longer hover the li so can't click on the button

        $('.next, .prev, .close').show();
        //add the hide of next prev to when you close the lightbox
    });

    $('.next').click(function() {
        currentIndex++;
        if (currentIndex == lightboxLis.length) {
            currentIndex = 0;
        }

        lightboxLis.hide();
        lightboxLis.eq(currentIndex).show();
    });

    $('.prev').click(function() {
        currentIndex--;
        if (currentIndex < 0) {
            currentIndex = lightboxLis.length - 1;
        }

        lightboxLis.hide();
        lightboxLis.eq(currentIndex).show();
      });

$('.close, #overlay').on("click", function() {
$('.close').hide();
overlay.hide();
$('.next, .prev').hide();
lightboxLis.eq(currentIndex).toggle();
});

});

When i click on sanita gallery and then on image, appears first image of maliarske a murarske práce. I need show light-box images only for sanita…
Really I don′t know how to fix it. I′m a beginner in custom theme and in jquery. If there is any similar click-trough gallery plugin with light-box I will appreciate it. Thanks a lot