I have a pop-up ice shelter which is in great shape, except that the black lining is wearing off the inside of its fabric. As a result, the shelter isn't as dark as I like it to be for sight fishing. Is there a flexible material which I can spray or paint on the inside of the shelter to bring back the darkness? I want to be able to say, like Simon and Garfunkel, "Hello darkness, my old friend! I've come to talk with you again!"