How to adjust the title size while scrolling

How to shrink the title while scrolling

First step - Add HTML:

Create the page header:

<div id="header">Header</div>

Second step - Add CSS:

Set the style of the page header:

#header {
  background-color: #f1f1f1; /* Gray background */
  padding: 50px 10px; /* Some padding */
  color: black;
  text-align: center; /* Centered text */
  font-size: 90px; /* Large font size */
  font-weight: bold;
  position: fixed; /* Fixed position - at the top of the page */
  top: 0;
  width: 100%; /* Full width */
  transition: 0.2s; /* Add transition effect (reduce font size during scrolling) */
}

Third step - Add JavaScript:

// When the user scrolls down 50px from the top of the document, adjust the font size of the title
window.onscroll = function() {scrollFunction()};
function scrollFunction() {
  if (document.body.scrollTop > 50 || document.documentElement.scrollTop > 50) {
    document.getElementById("header").style.fontSize = "30px";
  }
    document.getElementById("header").style.fontSize = "90px";
  }
}

Try It Yourself