Anyway so here's the problem... I can't find where to change the colour of the background of the reply box, and I also can't find where the border options are. For some reason on this style, the editor box has a border at the top and bottom, but not on the left or right. I've tried to find where to change this using firebug on one of the styles where this doesn't appear to be an issue but it's not being very helpful.
If anyone can help me with this, I'd really appreciate it because it's driving me a bit loopy right now lol.
Here's a screenshot, just in case you don't know what I'm referring to...