BASH Days until Christmas

#!/bin/bash
######################################################################
#Copyright (C) 2018  Kris Occhipinti
#https://filmsbykris.com

##Finds how many days until Christmas 2018

#This program is free software: you can redistribute it and/or modify
#it under the terms of the GNU General Public License as published by
#the Free Software Foundation, either version 3 of the License, or
#(at your option) any later version.

#This program is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#GNU General Public License for more details.

#You should have received a copy of the GNU General Public License
#along with this program.  If not, see <http://www.gnu.org/licenses/>.
######################################################################

function main(){
  echo "Welcome..."
  sleep 1
  while [ 1 ]
  do
    seconds="$(($(date --date "12/25/2018" +%s) - $(date +%s)))";
    clear;
    printf "%02d Days %02d Hours %02d Minutes and %02d Seconds Until Christmas\n"\
      "$((seconds/86400))" "$((seconds/3600%24))" "$((seconds/60%60))" "$((seconds%60))";
    sleep 1;
  done

  exit 0
}

main