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                <div class="contents">
  <a href="" target="_blank" class="button">解説を見る</a>


                .contents {
  height: 2000px;
  background-color: #ddd;

.button {
  position: fixed;
  right: 4%;
  bottom: 4%;
  display: flex;
  width: 120px;
  height: 120px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background-color: #0044cc;
  color: #fff;
  text-decoration: none;
  transition: 0.15s ease-in;
  &:hover {
    transform: translateY(4px);
  .is-scrollEnd & {
    transform: scale(0);


                const html = document.querySelector('html')
const bodyHeight = document.body.clientHeight // bodyの高さを取得
const windowHeight = window.innerHeight // windowの高さを取得
const bottomPoint = bodyHeight - windowHeight // ページ最下部までスクロールしたかを判定するための位置を計算

window.addEventListener('scroll', () => {
  const currentPos = window.pageYOffset // スクロール量を取得
  if (bottomPoint <= currentPos) { // スクロール量が最下部の位置を過ぎたかどうか
  } else {