davidfor it's an epub.
Since I'm used to media queries it's hard to accept that I can't have it both ways.
And it seems that I can't use a generic solution either, for all of the images.
The img { height: auto; width: 100%; } it worked for an image and it looks it adapts to the screen changes, but for the other images it doesn't. That is a mystery for me. I've also tried img { width: auto; max-height: 100%;} and img {max-width: 100%; height: auto;} and even if it changed the image's size in landscape mode, it was still broken.
It's like Kobo didn't recognise that is an image that should stay in one piece.
I'm getting tired of trying and I still didn't mention another problem that I have only in Kobo but not in iPad, and I'm not sure if I should start another topic...