CSS file / documentation

We should document the CSS details such as where the file is located, are there different files and for what purpose, etc.

Also while I am typing this .... where do I set the CSS for the table width. I did in Joomdle.com but couldn't find it again for my test server.

Again, I think this is a template thing, I think. Im my local copy with another template all tables get full width.

I search past emails and found this:
I had a look at the template CSS and found that by removing the 'width: auto;' line from .contentpane definition (in yoo_nu/css/joomla.css)

As you see, in theory this is a template thing, not Joomdle. As I said, I get full width with other templates.