Countdown doesnt work on php?

[balkan7]

i used php functions for datetime, php codes work perfectly but i add java script code for countdown minutes wait, doesnt work show nothing

 

code java script is:

<script language="JavaScript" type="text/javascript">
var theTime = document.getElementById('timer');
var sec = 01;   // set the seconds
var min = 10;   // set the minutes

function countDown() {
  sec--;
  if (sec == -01) {
    sec = 59;
    min = min - 1;
  } else {
   min = min;
  }
if (sec<=9) { sec = "0" + sec; }
  time = (min<=9 ? "0" + min : min) + " min and " + sec + " sec ";
if (document.getElementById) { theTime.innerHTML = time; }
  SD=window.setTimeout("countDown();", 1000);
if (min == '00' && sec == '00') { sec = "00"; window.clearTimeout(SD); location.reload(true); }
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}
addLoadEvent(function() {
  countDown();
});
</script>

 

php code for check time is:

<?php
if ($now < $check_date){

     echo "<div id='timer'></div>";
}?>

 

also did id corect for refresh page after minutes and seconds are 00:00 -> location.reload(true)