I have recently discovered the i3 window manager (after using Xfce). I first installed it on my laptop and all the window decorations (file/edit/view menus etc) looked horrible, and it was a light theme. I opened the Xfce-appearance menu and changed the theme and it applied (even to i3). Fast forward a few days and I want to install it on my desktop (Exact same install of Mint 18) and I can't get the theme to apply. Changing it does nothing.
TL;DR I don't know why changing the settings for Xfce worked on i3 for my laptop and I want to do the same but in a less hack-ish way for my desktop.