The real anniversary edition, for kids, seen further down in
this bbc story (if someone wants to link the picture, it was a bit too fiddly on my iPad) is perfectly fine. A variation of the regular current cover. This edition is just penguin adding the book to their modern classics range.
It's a bad cover. There are plenty of them about.
The typography and layout are exactly the same as all the other modern classics, as far as I can see, it's just a bad choice of image for the book.