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                <!DOCTYPE html>

  <meta charset="utf-8">
  <link rel="stylesheet" href="">
  <link rel="stylesheet" href="">
  <link rel="stylesheet" href="stylesheet.css">


  <section id="sns">
    <a href="" class="social-icon-btn instagram" target='_blank'><i class="fab fa-instagram"></i></a>
    <a href="" class="social-icon-btn twitter" target='_blank'><i class="fab fa-twitter"></i></a>
    <a href="" class="social-icon-btn facebook" target='_blank'><i class="fab fa-facebook-f"></i></a>




                #sns {
  text-align: center;
  display: flex;

.social-icon-btn {
  display: inline-block;
  /* ボタンを円形にする */
  width: 50px;
  height: 50px;
  border-radius: 50%;
  margin: 20px;
  /* SNSアイコンの色とサイズと位置 */
  color: white;
  font-size: 20px;
  padding-top: 15px;
  /* 透明度を0.7に */
  /*opacity を アニメーション対象とする */
  transition:opacity 1s;


/* 各SNSアイコンの背景色の設定 */
.instagram {
  background-color: #7d0188;

.twitter {
  background-color: #55acee;

.facebook {
  background-color: #3b5998;