That is not the best way I was dreaming of, but I can make it work.
1/ How can I also have this padding to the product page? When I add padding: 160px 0; to .single-product.postid-8594 .sh-titlebar it’s way too big.
2/ How can I add more then one? What’s the best way, let’s say 8595 and 8596 with the same image? Can I combine it to clean a bit my css ?