save project

snake.py

@@ -29,7 +29,7 @@ while True:
         score+=1
     else:
         pos.pop(0)
-        if x>0 or x<0
+        if x<0 or x>630 or y<0 or y>450
         
     # 将背景图画上去
     screen.blit(background, (0, 0))