Resolve "Next: PAT Edit Answers Date Picker"

Layout style problems

There's a vertical scroll on the page, as well as a white border at the bototm, when using the full-page layout. I was able to fix this, but with some hacky css, that I wasn't very happy with.

I left it as-is for now, as I think it's a bit out of scope for this issue, but we might want to consider refactoring the css around the full-page layout at some point, so it doesn't get so messy

Closes #501