Air vent question

My neighbor is getting a ton of leaves and maple tree helicopters in the air vent at the bottom of the windshield of his new Volkswagen Routan. He wanted me to sew some kind of cover for the windshield area that would extend over the vents. This would be used only while it’s parked in the driveway and would need to be easy on-off. My question is, does this thing exist already? Has anyone else had trouble with this and what have you done to solve this problem? Can you help me with a design idea? Thanks for any advice!

Its called a car cover. Try to Google it