#reg_form th {
    width: 10rem;
  }
  #reg_form td {
    width: 20rem;
  }
  #id_username, #id_email, #id_password, #id_reenter_password {
    width: 20rem;
  }
  
  @media screen and (max-width: 640px) {
    #id_username, #id_email, #id_password, #id_reenter_password {
      width: 90%;
    }
    .column {
      padding: 0;
    }
  }