default appearance to dark instead of system light

crates/theme/src/appearance.rs

@@ -12,11 +12,12 @@ use crate::{Theme, ThemeMode};
 /// it wherever their settings live; this crate never touches disk.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize)]
 pub enum AppearanceMode {
-    /// Follow the OS. The default — matches every other native app on the
-    /// machine, including when the OS is set to switch at sunset.
-    #[default]
+    /// Follow the OS — matches every other native app on the machine,
+    /// including when the OS is set to switch at sunset.
     System,
     Light,
+    /// Paint dark regardless of the OS.
+    #[default]
     Dark,
 }
 
@@ -62,7 +63,7 @@ pub fn init(mode: AppearanceMode, cx: &mut App) {
     Theme::change(resolve(mode, system), None, cx);
 }
 
-/// The mode currently in effect (defaults to `System` before [`init`]).
+/// The mode currently in effect (defaults to `Dark` before [`init`]).
 pub fn mode(cx: &App) -> AppearanceMode {
     cx.try_global::<AppearanceState>()
         .map(|state| state.mode)