Turn css pullup menu into a drop-line menu?

I know that one can make a list appear on a single horizontal line by using display:inline but I can’t get it to work on the two pullup menus in my footer menu (above Galleries and Wallpapers) on https://philipus.com.

The problem is I’m not sure which code I should include here to explain. I have tried adding the display:inline to virtually every part of the menu’s stylesheet I can think of (like the ul, li, etc).

Is there another way to do this or am I just not placing display:inline in the right spot?

/p