click this to go to the code
Your indentation drops from 2 spaces to 1 space.
I don’t know whether it is supposed to stay at 2 spaces or drop to zero
spaces, but half way is wrong and the interpreter is complaining.
Most people use four spaces for every indent level. The makes it more
obvious when the indentation changes. If you use a programmers text
editor, when you press TAB it will indent by four spaces, and when you
press SHIFT TAB it will dedent by four spaces.
What are you using to write your code?
The problem is in here:
while True: # --------Events---------- pygame.event.get() muisxy = pygame.mouse.get_pos() muisknoppen = pygame.mouse.get_pressed() #waar klik ik op # --------Draw------------ ## Achtergrond screen.fill(KleurBG)
Beginning with this line, the size of the indentation has decreased by one space:
EDIT (October 27, 2021):
Selecting the code makes it clear what happened.
You have some lines with no code, which is fine. However, note that they each contain only one space character, because you lost one space of indentation in the first of those lines. So when you started entering code again lower down, it was only indented by one space.