Based on the Tomorrow Night 1.0 by Justin Hileman for Coda 2 Editor
Of course, you need to have Nova installed (FYI, it only works under macOS).
If you're a proud owner of Nova, you ought to be able to go to Extensions > Extensions Library > Themes (tab) and pick the theme from there.
If that doesn't work, just clone this project (or download it from the releases page), it'll magically turn into a 'component' thingy, and you can then double-click it to add this theme to Nova!