diff --git a/settings/desktop.nix b/settings/desktop.nix
index c2f8a61..887d3ed 100644
--- a/settings/desktop.nix
+++ b/settings/desktop.nix
@@ -80,6 +80,14 @@
 
       dconf.settings."org/nemo/window-state".start-with-menu-bar = false;
 
+      # GTK3 ignores dconf's color-scheme=prefer-dark — it only picks
+      # adw-gtk3's gtk-dark.css when this setting is on. Without it GTK3 apps
+      # (nemo) load the *light* sheet; stylix's @define-color overrides repaint
+      # most of it, but colours sass baked in as literals survive — e.g.
+      # `messagedialog.csd.background button { color: rgba(0,0,6,0.8); }`, which
+      # is why nemo's delete confirmation had near-black buttons on dark bg.
+      gtk.gtk3.extraConfig.gtk-application-prefer-dark-theme = true;
+
       stylix.targets.gtk.extraCss = ''
         headerbar { min-height: 0; padding: 0; margin: 0; }
         headerbar .title { font-size: 0; }