diff --git a/packages/core/application/index.d.ts b/packages/core/application/index.d.ts
index 9d0106c3a..909627aa3 100644
--- a/packages/core/application/index.d.ts
+++ b/packages/core/application/index.d.ts
@@ -57,7 +57,7 @@ export const systemAppearanceChangedEvent: string;
 /**
  * Boolean to enable/disable systemAppearanceChanged
  */
-export let autoSystemAppearanceChanged = true;
+export let autoSystemAppearanceChanged: boolean;
 
 /**
  * enable/disable systemAppearanceChanged