<p id="countdown"></p>
body {
  background: orange;
  color: white;
}

#countdown {
  text-align: center;
  font-size: 80px;
  font: helvetica;
}
// Set the date we're counting down to
var countDownDate = new Date("Jan 1, 2020 00:00:00").getTime();

// Update the count down every 1 second
var x = setInterval(myFunction, 1000);
  
function myFunction() {

    // Get todays date and time
    var now = new Date().getTime();
    
    // 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("countdown").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("countdown").innerHTML = "EXPIRED";
    }
}

External CSS

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External JavaScript

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