<!DOCTYPE html>
<html lang="en">
<head>
<title>Title of page</title>
<style>
/* CSS styles here */
</style>
</head>
<body>
<p>Hello world!</p>
<script>
alert('Hello World!');
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<title>Title of page</title>
<style>
/* CSS styles here */
</style>
</head>
<body>
<p>Hello world!</p>
<script src="./main.js"></script>
</body>
</html>