style quirk with integration

My site is currently in the process of being redone (I sorta hit the self-detonate on accident when I was clearing out my webspace), so I can't actually show you it, but I'll try to describe it the best I can. I didn't see anything about it on the forum so maybe I'm just missing something.

When I made the thread to get feedback on my site, I had the following installed:
Joomla 1.0.12 (or is it 1.12? either way, it's the newest stable...not 1.5)
latest, stable CB module (I forgot the version sorry)
SMF 1.1.1

To bridge Joomla and SMF I used the 2.0.x bridge (again, the newest version). I installed the parts in the order described like the pdf advised to. When I was customizing the look of my site I noticed something peculiar. The style.css file for my forum themes seemed to override everything on the rest of my site, even the modules for Joomla.

The colors for links (new, active, visited) were all modified by that style.css as were many of the text colors and styles.

My question is, is this overlap supposed to happen or did I perhaps do something unaware that created a redundant code?

I do remember seeing some process of going through a css file for comment out some codes for html and body...although I never really understood it. Was that the cause of all this?

Edit:
I believe the MySQL on my host server is 4.x and I'm not sure what version my PHP is.
...and apparently someone doesn't like me :\ I just noticed the -1 karma.