Countdown Timer with HTML, CSS & JavaScript

02/05/2021
Demo
Video
Code
HTML
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>Countdown Timer with HTML, CSS & JavaScript</title>
<link rel="stylesheet" type="text/css" href="style.css">
</head>
<body>
<div class="time-container">
<div class="time"><p>Days</p><span id="days">00</span></div>
<div class="time"><p>Hours</p><span id="hours">00</span></div>
<div class="time"><p>Minutes</p><span id="minutes">00</span></div>
<div class="time"><p>Seconds</p><span id="seconds">00</span></div>
</div>
<script src="timer.js"></script>
</body>
</html>
CSS
@charset "utf-8";
@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@500&display=swap');
* {
box-sizing: border-box;
margin: 0;
padding: 0;
}
html {
font-family: 'Roboto', sans-serif;
font-size: 16px;
}
body {
display: flex;
justify-content: center;
align-items: center;
width: 100%;
height: 100vh;
background-color: #03031b;
}
.time-container {
display: flex;
justify-content: center;
}
.time {
display: flex;
flex-direction: column;
justify-content: center;
align-items: center;
margin: 0 15px;
color: #fff;
font-size: 1rem;
}
.time span {
margin-top: 10px;
color: #fac984;
font-size: 3rem;
}
@media screen and (max-width: 480px) {
.time {
font-size: 0.875rem;
margin: 0 8px;
}
.time span {
font-size: 1.75rem;
}
}
JavaScript
function countDown() {
const now = new Date();
const targetTime = new Date(`January 1, ${now.getFullYear() + 1} 00:00:00`);
const diff = targetTime - now;
const d = Math.floor(diff / (24 * 60 * 60 * 1000));
const h = Math.floor(diff / (60 * 60 * 1000)) % 24;
const m = Math.floor(diff / (60 * 1000)) % 60;
const s = Math.floor(diff / 1000) % 60;
document.getElementById('days').innerHTML = d;
document.getElementById('hours').innerHTML = ("0" + h).slice(-2);
document.getElementById('minutes').innerHTML = ("0" + m).slice(-2);
document.getElementById('seconds').innerHTML = ("0" + s).slice(-2);
}
setInterval(countDown, 1000);