We just got a 1 year old male Black and white from our local shelter. He does OK with everything except we have a sliding patio door that opens on to a raised deck with a 3'-0" high railing around the perimeter. We've had him out on the deck with us and he loves it but, now he has learned how to jump onto the railing and go down the stairs and we don't want to chase after him. We've tried one of those fabric harnesses and he HATES it and gets all tangled up in the cord. We've tried to keep him inside while we are on the deck but, he constantly claws and scratches at the glass on the sliding door trying to get out. We hate to leave him inside while we're on the deck. Any suggestions? HELP ! Thanks !