Custom CSS for Site Title, Tagline, and Menu

Hi. I'd like to edit my site title and tagline (and maybe my menu as well) to see what they would look like when centered. I'd also like to divide my tagline into 2 separate lines, if that's possible. I'm working here: http://029.b2b.myftpupload.com/ I'm not sure if my Custom CSS option is working? I tried entering a few lines of code there and nothing happened. Please advise.