diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..182ed0d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+__pycache__
+*.swp
\ No newline at end of file
diff --git a/button.py b/button.py
index cb368cd..99bd55c 100644
--- a/button.py
+++ b/button.py
@@ -1,39 +1,52 @@
 import pygame
 
-class Button():
+
+class Button:
     def __init__(self, screen, color, pos, width, height, text) -> None:
         self.pos = pos
-        self.größe = width,height
+        self.größe = width, height
         self.color = color
         self.screen = screen
         self.text = text
+
     def draw(self):
-        pygame.draw.rect(self.screen,
-                         self.color, 
-                        (self.pos[0]-self.größe[0]//2, 
-                         self.pos[1]-self.größe[1]//2, 
-                         self.größe[0], 
-                         self.größe[1])
+        pygame.draw.rect(
+            self.screen,
+            self.color,
+            (
+                self.pos[0] - self.größe[0] // 2,
+                self.pos[1] - self.größe[1] // 2,
+                self.größe[0],
+                self.größe[1],
+            ),
         )
-        pygame.draw.rect(self.screen,
-                        (0,150,0), 
-                        (self.pos[0]-self.größe[0]//2, 
-                         self.pos[1]-self.größe[1]//2, 
-                         self.größe[0], 
-                         self.größe[1]),
-                         2
+        pygame.draw.rect(
+            self.screen,
+            (0, 150, 0),
+            (
+                self.pos[0] - self.größe[0] // 2,
+                self.pos[1] - self.größe[1] // 2,
+                self.größe[0],
+                self.größe[1],
+            ),
+            2,
         )
-    
+
         font = pygame.font.Font(None, 30)
-        text_surface = font.render(self.text, True, (0,0,0))
+        text_surface = font.render(self.text, True, (0, 0, 0))
         text_rect = text_surface.get_rect()
-        text_rect.center = (self.pos[0], 
-                            self.pos[1])
+        text_rect.center = (self.pos[0], self.pos[1])
         self.screen.blit(text_surface, text_rect)
+
     def check_hovered(self, mouse):
-        if (self.pos[0] - self.größe[0]//2 <= mouse[0] <= self.pos[0] + self.größe[0]//2 and
-            self.pos[1] - self.größe[1]//2 <= mouse[1] <= self.pos[1] + self.größe[1]//2):
+        if (
+            self.pos[0] - self.größe[0] // 2
+            <= mouse[0]
+            <= self.pos[0] + self.größe[0] // 2
+            and self.pos[1] - self.größe[1] // 2
+            <= mouse[1]
+            <= self.pos[1] + self.größe[1] // 2
+        ):
             return True
         else:
             return False
-
diff --git a/main.py b/main.py
index 48df7ee..e4308b7 100644
--- a/main.py
+++ b/main.py
@@ -1,6 +1,7 @@
 #!/usr/bin/python3
 import pygame
-from button import *
+from button import Button
+from rules import pixel
 import copy
 import random
 
@@ -60,16 +61,7 @@ def verarbeite_feld(feld):
             for pos in finde_nachbarn(x, y):
                 if feld[pos[0]][pos[1]]:
                     lives += 1
-            if feld[y][x]:
-                if lives <= 1 or lives >= 4:
-                    new = False
-                else:
-                    new = True
-            else:
-                if lives == 3:
-                    new = True
-                else:
-                    new = False
+            new = pixel(feld[y][x], lives)
             feld2[y][x] = new
     return feld2  # gib kopie zurück
 
@@ -183,6 +175,11 @@ if __name__ == "__main__":
                     pause = not pause
                 if pressed_keys[pygame.K_r] and not before_pressed_keys[pygame.K_r]:
                     feld, feldx, feldy = make_feld(pixelsize, False)
+                if (
+                    pressed_keys[pygame.K_RETURN]
+                    and not before_pressed_keys[pygame.K_RETURN]
+                ):
+                    feld, feldx, feldy = make_feld(pixelsize, True)
 
         ## event managment
         for event in pygame.event.get():
diff --git a/rules.py b/rules.py
new file mode 100644
index 0000000..05a2c2a
--- /dev/null
+++ b/rules.py
@@ -0,0 +1,12 @@
+def pixel(state, lives):
+    if state:
+        if lives <= 1 or lives >= 4:
+            new = False
+        else:
+            new = True
+    else:
+        if lives == 3:
+            new = True
+        else:
+            new = False
+    return new