diff --git a/test.py b/test.py
index 58cd2f6..4aaa0db 100644
--- a/test.py
+++ b/test.py
@@ -103,9 +103,9 @@ class Bg:
             self,
             game:   Game,
     ):
-        self.base = BgBase (game)
-        self.jojoko = Jojoko (game)
         self.kita = KitaSun (game)
+        self.base = BgBase (game, self.kita.sun, layer = self.kita.layer - 5)
+        self.jojoko = Jojoko (game)
         self.grass = BgGrass (game)
 
 
@@ -284,23 +284,60 @@ class BgBase (GameObject):
     bg_evening: Surface
     bg_grass:   Surface
     bg_night:   Surface
-    surface:    Surface
+    sun:        Sun
 
     def __init__ (
             self,
             game:   Game,
+            sun:    Sun,
+            layer:  float,
     ):
-        super ().__init__ (game)
-        self.bg = pygame.image.load ('assets/bg.jpg')
-        self.bg_evening = pygame.image.load ('assets/bg-evening.jpg')
-        self.bg_grass = pygame.image.load ('assets/bg-grass.png')
-        self.bg_night = pygame.image.load ('assets/bg-night.jpg')
-        self.surface = pygame.transform.scale (self.bg, (CWindow.WIDTH, CWindow.HEIGHT))
+        super ().__init__ (game, layer = layer)
+        self.bg = self._load_image ('assets/bg.jpg')
+        self.bg_evening = self._load_image ('assets/bg-evening.jpg')
+        self.bg_grass = self._load_image ('assets/bg-grass.png')
+        self.bg_night = self._load_image ('assets/bg-night.jpg')
+        self.sun = sun
+
+    @staticmethod
+    def _load_image (
+            path:   str,
+    ) -> Surface:
+        return pygame.transform.scale (pygame.image.load (path),
+                                       (CWindow.WIDTH, CWindow.HEIGHT))
 
     def redraw (
             self,
     ) -> None:
-        self.game.screen.blit (self.surface, (self.x, self.y))
+        date_tmp = self.game.sky.observer.date
+        self.game.sky.observer.date = self.game.now.date ()
+        sunrise_start: datetime = (
+                (ephem.localtime (self.game.sky.observer.previous_rising (self.sun))
+                 - timedelta (minutes = 30)))
+        sunrise_end: datetime = sunrise_start + timedelta (hours = 1)
+        sunrise_centre: datetime = (
+                sunrise_start + (sunrise_end - sunrise_start) / 2)
+        sunset_start: datetime = (
+                (ephem.localtime (self.game.sky.observer.next_setting (self.sun))
+                 - timedelta (minutes = 30)))
+        sunset_end: datetime = sunset_start + timedelta (hours = 1)
+        sunset_centre: datetime = (
+                sunset_start + (sunset_end - sunset_start) / 2)
+        self.game.sky.observer.date = date_tmp
+        surface: Surface = ((self.bg
+                             if (sunrise_centre <= self.game.now < sunset_centre)
+                             else self.bg_night)
+                            .copy ())
+        if sunrise_start <= self.game.now < sunrise_end:
+            self.bg_evening.set_alpha (255 - int ((abs (self.game.now - sunrise_centre) * 510)
+                                                  / (sunrise_end - sunrise_centre)))
+        elif sunset_start <= self.game.now < sunset_end:
+            self.bg_evening.set_alpha (255 - int ((abs (self.game.now - sunset_centre) * 510)
+                                                  / (sunset_end - sunset_centre)))
+        else:
+            self.bg_evening.set_alpha (0)
+        surface.blit (self.bg_evening, (0, 0))
+        self.game.screen.blit (surface, (self.x, self.y))
         super ().redraw ()