That is quite impressive. Setting the perspective to 0 made the cover look like it was a front on shot but I could still see the side of the book which looks strange to me. Still nice though. edit: please take this as a helpful suggestion and not a criticism. I still really like the work you've done.
Thanks! Yes in CSS the perspective set to 0 basically removes all perspective (but for the pages it’s a different element in perspective, this is why you can still see it ;))