//eventListener
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>event listener</title>
<style>
body {
background-color: aquamarine;
}
button{
background-color:aquamarine;
border: 2px solid black;
border-radius: 5px;
cursor: pointer;
}
</style>
</head>
<body>
<h1 id="heading"> hi javascript </h1>
<button id="btn">Click</button>
<script>
let btn = document.getElementById("btn");
btn.addEventListener("click", () =>{
console.log("button was click");
heading.innerText="working";
});
</script>
</body>
</html>