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                <header class="header">
		<a href="" target="_blank">
			Cyd Stumpel
			Interaction observer example
<img src="" />



                * {
	font-family: 'Helvetica Neue', Helvetica, sans-serif;
	margin: 0;
	box-sizing: border-box;
	color: inherit;

a {
	text-decoration: none;

.header {
	width: 100%;
	height: 5.75rem;
	&.background--dark nav {
		background: black;
		color: white;
	nav {
		position: fixed;
		top: 0;
		left: 0;
		right: 0;
		display: flex;
		justify-content: space-between;
		width: 100%;
		font-size: 1.5rem;
		padding: 2rem;
		transition: 0.4s ease-out;
		@media (max-width: 750px) {
      font-size: 1rem;

img {
	width: 100%;
	heigth: 150vh;
	object-fit: cover;


                const header = document.querySelector('.header');
const inView = (entries) => {
  for (const entry of entries) {
    // try logging entry to view all the possible values
    if (entry.boundingClientRect.y < -32) {
      header.classList.add('background--dark'); // for example change the background of the header when the page has scrolled 32 px.
    } else {
// threshold is just one of the options you can pass in the InteractionObserver
// It determines the amount of triggers while scrolling, it allows an array of numbers between 0 and 1
let threshold = []; 
for (let i = 0; i <= 100; i++) {
  threshold.push(i / 100);

const observePageHeader = new IntersectionObserver(inView, { threshold });

// observing the element that has .header as a class