@ Jack
First, you should take a moment and read this QuickTip thoroughly … its important because this is the best way to load custom CSS files for a template in an update safe way.
Now, most font related styles ares inherited by the theme that is where the current font color and font family is being set, it is not part of Connections or cMap. The size is and can be overridden with this:
#cn-cmap .fn {
font-size: inherit;
}
As for what other classes there are, you’re going to have to use the dev tools (F12) in the browser of your choice (mine is Chrome and IE11) to look for the ones that you want to change. I can’t really list them out because everything Connections renders on page is classed so it can be selected with CSS. It would take me several hours to find and list out every class being used.
I hope that helps!