Showing a hidden part of the page after the javascript timer ends

Question

I want to be able to hide a part of the website with a timer and after that timer ends the users be able to see the hidden part
this is the script ive done so far

// Set the date we're counting down to
var countDownDate = new Date("Jan 5, 2022 15:37:25").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 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);

  // Display the result in the element with id="demo"
  document.getElementById("demo").innerHTML = hours + "h " +
    minutes + "m " + seconds + "s ";

  // If the count down is finished, write some text
  if (distance < 0) {
    clearInterval(x);
    document.getElementById("demo").innerHTML = "EXPIRED";
  }
}, 1000);

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

Answer 1

Just show the div

You can remove a class or change the display or change .hidden

// Set the date we're counting down to
var countDownDate = new Date();
countDownDate.setTime(countDownDate.getTime() + 5000); // demo

// 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 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);

  // Display the result in the element with id="demo"
  document.getElementById("demo").innerHTML = hours + "h " +
    minutes + "m " + seconds + "s ";

  // If the count down is finished, write some text
  if (distance < 0) {
    clearInterval(x);
    document.getElementById("demo").innerHTML = "EXPIRED";
    document.getElementById("hidden1").classList.remove("hide");
    document.getElementById("hidden2").style.display = "block";
    document.getElementById("hidden3").hidden=false;
  }
}, 1000);

.hide {
  display: none;
}

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

<div id="hidden1" class="hide">Show this when expired (class)</div>
<div id="hidden2" class="hide">Show this when expired (display)</div>
<div id="hidden3" hidden>Show this when expired (hidden)</div>