Thanks, thesacredpath. This really helped a lot. And I think I figured a few things out. In regards to widths and columns, I still have two remaining questions: 1) I switched the layout back to three columns. I am able to control the widths of the content and primary sidebar (on the right), but cannot seem to control the secondary sidebar. Might this secondary one have a different code name that I am not getting? and 2) I still can't seem to widen the entire theme. Could you explain that one more time? Thanks!
Also, and this is a little off-topic. But, I have attempted to switch the color of my navigation links to gray with this code:
On the preview site, everything works great. And yet, after I save it and return to my actual blog, only about half of the links have turned gray. What might I be missing here?
And honestly, thanks so much for your help. Sorry to be a bundle of questions. Very new to CSS! Thanks.