The background image has a fixed position on the page. For instance, when you scroll down the page, the background image occupies the same space regardless of where you've scrolled. This is breaking most designed Google Sites.
|The footer is eating my content. Help!|
The Google Sites help forums are totally abuzz with complaints, probably fueled by customers/clients pestering their web designers. This is a huge problem that came out of nowhere and has many designer caught off-guard.
It has been escalated to Google representatives.
|This isn't good...at all.|
The whole issue calls into question the Google Sites team's beta-testing of updates and truthfully whether they test at all. This problem is readily visible and annoying.
On the other hand, perhaps this means that Google is working on a new patch to the Google Sites platform, more specifically in the design field. This has happened before. I know people have asked for the ability to create a fixed background image, like in blogger, before. Maybe that's it.
Overall, bear with the inconvenience and hope for a quick-fix, instead of a 'working as intended' (hopefully not!).
Here's my post on the forums if you wish to chime in: https://groups.google.com/a/googleproductforums.com/d/topic/sites/tvlVGnJJ_3s/discussion