diff --git a/tools/mks.c b/tools/mks.c
index 108b7e7..4b30fb6 100644
--- a/tools/mks.c
+++ b/tools/mks.c
@@ -65,6 +65,7 @@ main (int   argc,
   g_autoptr(GError) error = NULL;
   GtkWindow *window;
   GtkWidget *display;
+  GtkSettings *settings;
   GdkSurface *surface;
 
   gtk_init ();
@@ -79,10 +80,15 @@ main (int   argc,
   main_loop = g_main_loop_new (NULL, FALSE);
 
   window = g_object_new (GTK_TYPE_WINDOW,
-                         "default-width", 640,
-                         "default-height", 480,
+                         "default-width", 1280,
+                         "default-height", 768,
                          "title", "Mouse, Keyboard, Screen",
                          NULL);
+
+  settings = gtk_settings_get_default ();
+  g_object_set (settings, "gtk-application-prefer-dark-theme", TRUE, NULL);
+  gtk_widget_add_css_class (GTK_WIDGET (window), "dark");
+
   display = mks_display_new ();
   gtk_window_set_child (window, display);
   g_signal_connect_swapped (window,