Add blank line between pages/link

Recently, I bought the COLr theme from Horizonalwp because it was exactly what I was looking for. I runs just fine, but there’s one ‘problem’ – I can’t seem to figure out how to add the ‘blank/white’ ‘space’ between links/pages/menu items (like in the demo, between “Winter” and “about”). I’ve tried contacting the maker, but to no avail. My customised menu is now just a bunch of links thrown together, without much of organisation or hierachy. Is there anyone who can help me figure this out and/or tell me how to do this?

Thank you.