initial-test.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="intial-test.css">
    
</head>
<body>
    <script>

    </script>
    <div id="viewport">
        <div id="camera">
            <div id="scene">
                <!-- silence is golden -->
            </div>
        </div>
    </div>
</body>
<script src="initial-test.js"></script>
</html>