forever: "lift up" content closer to menu

Hi all, I’m starting to dive into the CSS, and hoping for a little help.
I’m noticing a huge gap, between the menu and the top of the content.
I see the Id’s from #menu to #content, but not to sure in the css area, the variable used to push everything up? There’s noticeable gaps between #menu and #primary. from #primary to #content, and from #content to class: entry-content

what variable to I use to figure out how to push things up?

thanks!