@keyframes shine {
  0% {
    transform: scale(0) rotate(45deg);
    opacity: 0;
  }
  80% {
    transform: scale(0) rotate(45deg);
    opacity: 0.5;
  }
  81% {
    transform: scale(4) rotate(45deg);
    opacity: 1;
  }
  100% {
    transform: scale(50) rotate(45deg);
    opacity: 0;
  }
}

/*GA4用タグ追加*/

<!-- Google tag (gtag.js) -->
<script async src="https://www.googletagmanager.com/gtag/js?id=G-ZGCPLPBVN3"></script>
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('js', new Date());

  gtag('config', 'G-ZGCPLPBVN3');
</script>