To shrink a header on scroll with CSS and JavaScript, the code is as follows −
Example
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1" />
<style>
body {
font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
margin: 0px;
padding: 0px;
height: 150vh;
}
.header {
position: fixed;
top: 0;
width: 100%;
background-color: rgb(52, 21, 110);
color: white;
padding: 50px;
font-size: 40px;
transition: 0.8s;
}
</style>
</head>
<body>
<div class="header">Header Text</div>
<p style="font-size: 35px;">
Lorem ipsum dolor sit amet, consectetur adipisicing elit. Odit vel dolore delectus
esse consequatur at nulla, consequuntur sint quas ea. Incidunt, ex. Consequatur ipsa
earum veritatis fugiat iusto, doloremque sunt beatae quaerat laboriosam nemo soluta
quidem porro quia. Dolore reprehenderit cum
voluptatibus eius assumenda ipsam tenetur asperiores magni aliquid eligendi doloribus
quidem ipsa et praesentium provident molestias quaerat laboriosam, veniam aspernatur
repellendus. Debitis sapiente, odit iste voluptatibus nesciunt veritatis incidunt
mollitia nostrum, vitae suscipit iusto molestias consequuntur rem facere perspiciatis
ad! Ratione reiciendis asperiores aperiam vitae facilis accusantium non aliquid, facere
cupiditate reprehenderit tempore veritatis eum accusamus omnis
tempora quos!</p>
<script>
window.onscroll = function() {resizeHeader()};
function resizeHeader() {
if (document.body.scrollTop > 50 || document.documentElement.scrollTop > 50) {
document.querySelector(".header").style.fontSize = "20px";
} else {
document.querySelector(".header").style.fontSize = "40px";
}
}
</script>
</body>
</html>Output
The above code will produce the following output −
On scrolling down a little the header font size will shrink as follows −
