a brutal and straightforward minimalist theme ever. Taking inspiration from all over the internet wonderland. I have beeing using this myself for like years now. No issue so far. If found any groups you need and not in it, you can fork it and improve on it.
Theme under: https://github.com/kenken17/minimal.vim
Use any of your plugin managers should not be any issue. I am using vim-plug myself. So did not test on other. If there is issue on any other plugin managers, you can leave a message, I will try to look into it.
Plug 'kenken17/minimal.vim'
Nothing much is needed except using it on .vimrc:
colorscheme minimal
MIT