For the past day or so I've been fiddling around with i3 and I like the functionality it offers. I know themeing i3 to the point where it looks like a modern DE is possible, and I've been following a guide, but I can't find anything on getting things pretty on an out-of-the-box install - not from a system that had a DE on it. I installed i3 from Raspbian Lite. My windows look like this - the terminal on the left is supposed to be gnome-terminal which I consider to be pretty, but what I see isn't. Why do my windows look like this and what do I need to do to make them look "normal"?

Update: I installed a theme (Arc Dark), and it definitely made things better! Click
One of the issues is the weird spacing (or lack thereof) on the File Edit View [...] buttons. How do I fix those?