{
  lib,
  config,
  pkgs,
  system,
  ...
}: let
  inherit (lib) mkEnableOption mkIf;
  inherit (lib.snowfall.system) is-linux;
  inherit (lib.marleyos) enabled;

  cfg = config.marleyos.appearance.base;
  inherit (config.marleyos.theme) colors;
  inherit (config.marleyos) isDesktop;
in {
  options.marleyos.appearance.base.enable = mkEnableOption "base";

  config = mkIf cfg.enable {
    home.packages = with pkgs; [
      # TODO: package font with harfbuzz features.
      maple-mono-NF
      dm-sans
      eb-garamond
      whatsapp-emoji-font
    ];

    rose-pine.pointerCursor = mkIf colors.isRosePine enabled;

    marleyos.theme = {
      colors = {
        default = "dark";

        dark = {
          base = "rose-pine";
          flavor = "main";
        };

        light = {
          base = "rose-pine";
          flavor = "dawn";
        };
      };

      icons = {
        package = pkgs.kora-icon-theme;
        name = "kora";
      };

      pinentry =
        if isDesktop
        then pkgs.pinentry-gtk2
        else pkgs.pinentry-curses;
    };

    fonts.fontconfig = mkIf (is-linux system) {
      enable = true;
      defaultFonts = {
        monospace = ["Maple Mono NF"];
        sansSerif = ["DeepMind Sans"]; # dm-sans
        serif = ["EB Garamond"];
        emoji = ["Apple Color Emoji"]; # whatsapp-emoji-font
      };
    };
  };
}