My bathroom door cannot swing shut because of a bath mat. It needs to have about 1/8" to 3/8" shaved off the bottom of the door in order for the door to freely open and close without the bath mat getting in the way. What is the best way to trim the bottom of the door? It is my understanding that the door is hollow with trim around the edges that hold the door together. If I cut the bottom, it can break the trim off and cause the door to split apart?? I'm trying to understand the best way to trim the door without breaking it apart and causing myself and ton of headaches. Thanks for any help.