Question: Thread backgrounds

[Peeky Chew]

I've noticed a few threads with nice backgrounds to their text/images etc. Like this:
https://www.pokecommunity.com/threads/200683
I was just wondering how you do this, and where I coud get some nice ones?

Thanks :)

 

[jigglyppuff8]

It was made using a form of Cascading Style Sheets (CSS) made for the forums. A guide and help thread to using it on PokeCommunity can be found here.

 

[Peeky Chew]

I don't really understand most of that so I guess I'll just stick to normal posting...
The bit that doesn't make sense is that on the background color code it uses none of these [ = / ]