The pattern on the left is actually just inside the case, under a clear part of the case. That part is black in the Euro version, but the case looks the same otherwise. (We have cases like that, too.)
Edit: Also, that Japanese one? I’m pretty sure it’s the same style, but turned upside down. That’s the base of the case. Searching Google, I found a copy on Ebay that shows the front, and that section of the front of the case is clear for that one, too.
The grooves?
The pattern on the left is actually just inside the case, under a clear part of the case. That part is black in the Euro version, but the case looks the same otherwise. (We have cases like that, too.)
Edit: Also, that Japanese one? I’m pretty sure it’s the same style, but turned upside down. That’s the base of the case. Searching Google, I found a copy on Ebay that shows the front, and that section of the front of the case is clear for that one, too.