We recently renovated our house. We don't have a porch area, we have a very narrow hallway were we have placed a small shoe rack. Couple steps after the shoe rack is the living room and lounge. The frustrating problem is this:Due to some miscalculation by the builders, we have less than a centimeter gap between the bottom of the front door and the floor. So we can't place any door mat. We do have a rough mat outside the house. We have a dog. On wet/muddy days, our shoes and our dog's paws all get really muddy and you can imagine the hall way looks really nasty. I make it a point to rub the floor every time someone come in from outside, I wish there is something we can do about it. Any ideas please