显示不同时区的倒计时

问：

我正在运行一个倒数计时器，用于 3 个时区（GMT、PT、EST），我需要它进行同步，以便每个时区的计时器在同一时间结束。这是我下面的代码。这是时间敏感的（没有双关语），所以提前感谢！

     <p id="demo"></p>

<script>
// Set the date we're counting down to
var countDownDate = new Date("Nov 17, 2023 20:00:00").getTime();

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

  // Get today's date and time
  var now = new Date().getTime();
    
  // Find the distance between now and 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 = 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>