diff --git a/common_const.py b/common_const.py
index 7f32eb1..f940ab5 100644
--- a/common_const.py
+++ b/common_const.py
@@ -1,7 +1,7 @@
 from pydantic import BaseModel
 
 
-class Window (BaseModel, frozen = True):
+class CWindow (BaseModel, frozen = True):
     WIDTH: int = 1024
     HEIGHT: int = 768
 
diff --git a/main.py b/main.py
index 6dce626..3456874 100644
--- a/main.py
+++ b/main.py
@@ -37,11 +37,12 @@ class Main:
 
         # ウィンドゥの初期化
         pygame.init ()
-        screen: pygame.Surface = pygame.display.set_mode ((Window.WIDTH, Window.HEIGHT))
+        screen: pygame.Surface = pygame.display.set_mode (
+                (CWindow.WIDTH, CWindow.HEIGHT))
 
         # 吹き出し
         balloon = pygame.transform.scale (pygame.image.load ('talking.png'),
-                                          (Window.WIDTH, 384))
+                                          (CWindow.WIDTH, 384))
         if goatoh_mode:
             balloon = pygame.transform.flip (balloon, False, True)