<!DOCTYPE html>
<html lang="ja">
<head>
    <meta charset="UTF-8">
    <title>DOM操作サンプル (onclick)</title>
</head>
<body>
    <p id="message">こんにちは！</p>
    <button id="toggle" onclick="run()">ボタン</button>
    <script src="script.js"></script>
</body>
</html>