nixos/cosmic: set default cursor theme

nix-os/desktopManagers/cosmic.nix

@@ -1,4 +1,10 @@
-{ inputs, lib, pkgs, ... }:
+{
+  inputs,
+  lib,
+  pkgs,
+  self,
+  ...
+}:
 
 let
   cosmic-configuration = pkgs.substituteAllFiles {
@@ -20,6 +26,7 @@ in
 {
   imports = [
     "${inputs.cosmic-modules}/nixos/cosmic/module.nix"
+    "${self}/nix-os/generic/dconf.nix"
   ];
   config = {
     services.desktopManager.cosmic.enable = true;
@@ -29,7 +36,26 @@ in
     ];
     environment.systemPackages = with pkgs; [
       (lib.hiPrio cosmic-configuration.share)
+      google-cursor
     ];
     services.gnome.gnome-keyring.enable = true;
+
+    proot.dconf = {
+      rules."org/gnome/desktop/interface".cursor-theme = "GoogleDot-White";
+      profiles.user.rulesToApply = [
+        "org/gnome/desktop/interface"
+      ];
+    };
+
+    environment.sessionVariables = {
+      XCURSOR_SIZE = "16";
+      XCURSOR_THEME = "GoogleDot-White";
+    };
+
+    environment.etc."xdg/gtk-3.0/settings.ini".text = ''
+      [Settings]
+      gtk-cursor-theme-name=GoogleDot-White
+      gtk-application-prefer-dark-theme=true
+    '';
   };
 }