Seeing pages in "shades"
I realise the thread title doesn't make a lot of sense, so let me explain myself.
I read music and, while I'm looking at a piece, I perceive the second page as being darker than the first. The third page is similar to the second, then the fourth page gets brighter again. A similar thing happens with forums. For instance, I perceive General Autism Discussion to be lighter than Social Skills and Making Friends. It's pretty bizarre, but I've always "done" this. Oddly, it doesn't happen for books (unless they're music books) or most other materials. It doesn't seem to happen on any websites besides forums, either.
So, anyone else have anything similar? I'm wondering if it's maybe some bizarre kind of synesthesia. Or maybe everyone is like this and I'm just being silly.