Broken dark theme

Steps to reproduce

1. Log in to demo.funkwhale.audio
2. Switch the theme to "Dark"

What happens?

The theme does not fully switch. Backgrounds stay light and only minor elements such as font colour are affected

What is expected?

The theme should switch fully to the dark theme

Context

Funkwhale version(s) affected: 0.20.1+git.cfe7317f