The blue is fine. The grey bar running under the signatures is strange though...
The line above the signature? Or the Bar Above the post that has todays date and post number on it?
The gray bar is to separate post content from signatures... You've seen sites where the break isn't clear and you're 5 words into the signature before you realize you've read that 1,000 times before.
The Blue Bar is to separate and define individual posts. Those do need to be dark as they are the horizontal separators when scrolling. The eye sees it as posts, instead of a long sheet of flat info with a bunch of posts somewhere in there.
We can change the color of each, but they need to remain dark, and in the same color spectrum as the rest of the forum.