How do I display javascript timer with PHP

<pre><?php


//including the database connection file
include("config.php");

$conn= mysqli_connect("localhost", "root", "", "live");

$result = mysqli_query($mysqli, "SELECT * FROM timer ORDER BY id DESC");
while($res = mysqli_fetch_array($result)) { 
$date = $res['date'];
$h = $res['h'];
$m = $res['m'];
$s = $res['s'];
}

if(isset($_POST['submit'])){

    echo "
    <p id='demo'>
<script>
var countDownDate =  * 1000;
var now =  * 1000;

// Update the count down every 1 second
var x = setInterval(function() {
now = now + 1000;
// Find the distance between now an the count down date
var distance = countDownDate - now;
// Time calculations for days, hours, minutes and seconds
var days = Math.floor(distance / (1000 * 60 * 60 * 24));
var hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
var minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
var seconds = Math.floor((distance % (1000 * 60)) / 1000);
// Output the result in an element with id='demo'
document.getElementById('demo').innerHTML = days + 'd ' + hours + 'h ' +
minutes + 'm ' + seconds + 's ';
// If the count down is over, write some text 
if (distance < 0) {
clearInterval(x);
document.getElementById('demo').innerHTML = 'EXPIRED';
}
   
}, 1000);

   </script></p>
";}




?>