Padding under images

It isn’t my site, but you can see it here, scroll to the image with a boat, padding is 5px, but padding-bottom is more than padding top, left and right.

Yes, I’ve seen that, padding: 5px. But as I said before, it’s 5px at the top, left and right, but padding-bottom is more than 5px. So how is that possible?

Then it’s ok for new posts written with Gutenberg, but all the old ones have strange borders.

I’m testing on a local installation, so I can’t. But I’ve found a solution meanwhile, I changed

.alignleft, .alignright, .aligncenter, .alignnone {
 border: 1px solid #ccc;
}

to

img[class*="align"],
img[class*="wp-image-"] {
	border: 1px solid #ccc;
}

and now there is no more padding on any side anymore.
Thanks for your help!