Armadillo and CSS on navigatin stack

to be honest: I am not good in CSS! See following website (and then the blog). We would like the navigations stack to behave differently then it does now. Somehow only when I make the page sizewise small it will list the tags, months an categories under eachother. But mostly it displays blocks next to eachother.

What would be the correct CSS to get it under eachother ? (and also is there a way to make the font a bit bigger?. Any help is much appreciated. I was already thrilled I got it up and running for novice like me with MySQL etc :wink:

http://www.starobserver.eu

thanks

MJ