vim-colors-plain is a duotonic color scheme, the two accents being cyan and pink by default (configurable).

i would suggesting installing manually by cloning into your plugin directory or dropping colors/plain.vim into one of the following directories:

• vim: .vim/plugin
• neovim: .config/nvim/plugin

if you use nix/nixos, this repository provides a vim plugin as a flake output, that you can import via builtins.getFlake.

vim-colors-plain = {
  url = "github:oppiliappan/vim-colors-plain";
  inputs.nixpkgs.follows = "nixpkgs";
};

  .
  .
  .

programs.neovim.plugins = [ pkgs.vim-colors-plain ];