<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>

        body {
            height: 100%;
            margin: 0;
            padding: 0;
        }

        div{
            height: 1000px;
        }
    </style>
</head>
<body>
<div>
    aaaaa
</div>
</body>
</html>
<script src="px2.js"></script>
<script src="mouse.js"></script>