Demo

<!DOCTYPE html>
<html>
	<head>
		<title>Details/summary</title>
	</head>
	<body>
		<h1>Details/summary are interactive</h1>
		<details>
			<summary>Clicking this toggles the element</summary>
			<p>You can have any content down here.<p>
			<p>Multiple elements, whatever you want.<p>
		</details>
		<details open>
			<summary>They also can be open to start</summary>
			<p>This will already be visible.<p>
		</details>
	</body>
</html>