You might have assumed that Nanase removed her sunglasses due to them having entered a cave, and thought yourself quite clever, but no.
It's because stuff like this happens.
I feel "strike" is as good a sound effect as any for this. I'm not sure what else I would use for the sound of bowling pins being hit by a bowling ball, let alone stone pillars knocked over by a spherical Nanase.
I did reference bowling strikes to help with the first panel, however, and I have concluded something about strikes: The laws of physics have nothing to do with the movement of the pins.
It is witchcraft.