If you see to the browser console you will see many errors. Almost all of them are because an image was not found in the server, but there are others.
The images not found are because they have bad URL:
http://produkcja.adlike.pl/images/index_img05.jpg
instead of
http://produkcja.adlike.pl/public_html/produkcja/wp-content/themes/Mywordpresstheme/images/index_img05.jpg
There is only one that seems to have correct URL and is getting an error: http://produkcja.adlike.pl/public_html/produkcja/wp-content/themes/Mywordpresstheme/images/index_img03.jpg
I think it can be caused by the other errors or because you are implementing a responsive images script, incorrectly (I see you have data-src in your images)