.fadein {
  /* 最初は非表示 */
  opacity: 0;
  visibility: hidden;
  -webkit-transform: translateY(30px);
  transform: translateY(30px);
  -webkit-transition: opacity 1s, visibility 1s, -webkit-transform 1s;
  transition: opacity 1s, visibility 1s, -webkit-transform 1s;
  transition: opacity 1s, visibility 1s, transform 1s;
  transition: opacity 1s, visibility 1s, transform 1s, -webkit-transform 1s;
}

/* フェードイン時に入るクラス */
.is-fadein {
  opacity: 1;
  visibility: visible;
  -webkit-transform: translateX(0);
  transform: translateX(0);
}