<!DOCTYPE html>
<html>
<body>
<h2>JavaScriptの作成</h2>
<p>オブジェクトの作成</p>
<p id="demo"></p>
<script>
const person = {};
person.firstName = "John";
person.lastName = "Doe";
person.age = 50;
person.eyeColor = "blue";
document.getElementById("demo").innerHTML =
person.firstName + " は " + person.age + " 歳です。";
</script>
</body>
</html>
