Added some dialogs for transitions

src/Game.h

@@ -51,6 +51,7 @@ namespace ZL {
 		bool isDarklands = false;
 		// Returns false if a transition is already in progress.
 		bool startDarklandsTransition();
+		bool startNightTransition();
 
 		Inventory inventory;
 		InteractiveObject* pickedUpObject = nullptr;
@@ -118,10 +119,11 @@ namespace ZL {
 		static void onResourcesZipError(const char* filename);
 #endif
 
-		// White-flash transition state
+		// Screen-flash transition state (shared by darklands and night transitions)
 		float darklandsFlashAlpha = 0.0f;
 		bool  darklandsFlashActive = false;
 		bool  darklandsFlashFadingIn = true;
+		bool  isNightTransition = false;  // true → black flash toggling isNight; false → white flash toggling isDarklands
 		VertexRenderStruct darklandsFlashQuad;
 		float darklandsFlashQuadW = -1.0f;
 		float darklandsFlashQuadH = -1.0f;