nixos-config/config/programs/theming.nix

{ pkgs, ... }: {
  gtk.enable = true;
  gtk.iconTheme.package = pkgs.numix-icon-theme;
  gtk.iconTheme.name = "Numix Dark";
  gtk.theme.package = pkgs.libsForQt5.breeze-gtk;
  gtk.theme.name = "Breeze Dark";

  # Paraiso (dark) by Chris Kempson
  # Alacritty colors
  programs.alacritty = {
    enable = true;
    settings = {
      colors = {
        # Default Colors
        primary = {
          background = "0x2f1e2e";
          foreground = "0xa39e9b";
        };

        # Normal Colors
        normal = {
          black = "0x2f1e2e";
          red = "0xef6155";
          green = "0x48b685";
          yellow = "0xfec418";
          blue = "0x06b6ef";
          magenta = "0x815ba4";
          cyan = "0x5bc4bf";
          white = "0xa39e9b";
        };

        # Bright Colors
        bright = {
          black = "0x776e71";
          red = "0xef6155";
          green = "0x48b685";
          yellow = "0xfec418";
          blue = "0x06b6ef";
          magenta = "0x815ba4";
          cyan = "0x5bc4bf";
          white = "0xe7e9db";
        };
      };
    };
  };
}