Suite R theme - how do I decrease the vertical line spacing/padding in listviews and dashlets?

I’m still using the Suite R theme, as I love its relative compactness and clean look.

I am wanting to increase the number of lines visible in dashlets and in list views, by decreasing the vertical spacing/padding of each line (to put the lines closer together).

I’m assuming this is a css change, but can anyone point me in the right direction?

Many thanks!
Paul