tree.html

<html>
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <script src="data.js"></script>
    <script src="svgdom.js"></script>
    <script src="maketree.js"></script>
    <style>
        body
        {
            margin: 0;
        }
        #tree
        {
            margin: 0 auto;
            display: block;
            width: 100%;
            height: auto;
            max-height: 800px;
        }
        #explanation
        {
            margin: 20px;
            text-align: center;
        }
    </style>
</head>

<body>
    <svg id="tree" viewBox="0 0 400 400">
        <style>
            tspan {
                cursor: pointer;
                font-family: 'Times New Roman', Times, serif;
            }
        </style>
    </svg>
    <div id="explanation"></div>
    <script>
        drawTree();    
    </script>
</body>
</html>