The newest 7.x-4.0 version of the Answers module comes with the (new) Answers Theme
sub-module, which, out-of-the-box, transforms the (rather boring) vanilla display of a Question (and its related Answers below it), into a way more attractive look-and-feel. Such as the orange bubble that is added around the question (to better highlight it). Here is a screenprint that is pretty close to what's included in the newest version:
If you don't enable this sub-module, then you get a similar vanilla display (still). To see it at work, head over to this example question in its demo site).
With this submodule enabled, it might no longer be needed to makeg the background color of the answer content type a different color (to distinguish it from the question to view both the answers and the question on the same page), since they don't look the same anymore, already out-of-the-box. Though you could still adapt the CSS (eg the orange bubble) to fit your preferences.
Disclosure: I'm a co-maintainer of Answers.