CSS for commentarea

I’m having trouble understanding how the CSS for the comments works. In particular, I do not seem to be able to change the font size within the comment areas. I have looked at the annotated style sheet, which is excellent, and tried to adjust the font size in the commentarea but with no luck.
I’m wondering, does the CSS id=comment-1 have any influence?
If someone can explain exactly where to style these elements I would be most greatful.
My site is at http://wp.jeremycherfas.net/
Thanks