I have a picture problem on my site. If I put a big picture, its proportions change. You can see it here: http://dolinaraby.pl/zyczenia-wielkanocne-2/ At first I did not realize that this is so but...

Hi, I'm having trouble with images posted directly to wordpress pages and posts. In the laptop, tablet, mobile view, they are stretching. I've set them to be responsive, changed the post images sizes...