The Hugo theme will also generate a counterpart system theme if there's
only one system theme given. Though, it isn't perfect so the release
will not happen for a while. I'll look into generating a color palette
with HSLuv to see if it can be improved.
It should be easier to integrate it with other libraries such as Prism,
Mermaid, and D3 especially in the graphics department where it mostly
use vector graphics to do its thing.
