<h1>simpleParallaxデモ</h1>
    <h2>基本の設定</h2>
<div class="box">
  <img class="thumbnail" src="https://pengi-n.co.jp/blog/wp-content/uploads/2024/01/penguin2.jpeg" alt="image">
</div>

* {
	box-sizing: border-box;
	margin: 0;
	padding: 0;
}

h1 , h2 {
	text-align: center;
}

h1 {
	margin-top: 30vh;
}

.box {
	border: 5px double #333;
	height: 50vw;
	margin: 100px auto 200px;
	overflow: hidden;
	width: 80%;
}

.thumbnail {
	width: 100%;
}

const image = document.getElementsByClassName('thumbnail');
new simpleParallax(image);