<!--スライダー-->
<div class="swiper">
  <div class="slider swiper-container">
    <div class="swiper-wrapper">
      <div class="swiper-slide slide1">
        <p>スライド1</p>
      </div>
      <div class="swiper-slide slide2">
        <p>スライド2</p>
      </div>
      <div class="swiper-slide slide3">
        <p>スライド3</p>
      </div>
      <div class="swiper-slide slide4">
        <p>スライド4</p>
      </div>
      <div class="swiper-slide slide5">
        <p>スライド5</p>
      </div>
      <div class="swiper-slide slide6">
        <p>スライド6</p>
      </div>
    </div>
    <div class="swiper-button-next"></div>
    <div class="swiper-button-prev"></div>
  </div>
</div>
<!-- サムネイル -->
<div class="swiper-thumbnail swiper-container">
  <div class="swiper-wrapper">
    <div class="swiper-slide slide1">
      <p>スライド1</p>
    </div>
    <div class="swiper-slide slide2">
      <p>スライド2</p>
    </div>
    <div class="swiper-slide slide3">
      <p>スライド3</p>
    </div>
    <div class="swiper-slide slide4">
      <p>スライド4</p>
    </div>
    <div class="swiper-slide slide5">
      <p>スライド5</p>
    </div>
    <div class="swiper-slide slide6">
      <p>スライド6</p>
    </div>
  </div>
</div>
/*コンテナ要素のスタイル*/
.swiper-container {
  width: 100%;
  height: 200px;
  margin: 0.5rem auto;
  overflow: hidden;
}

/*各スライドのスタイル*/
.swiper-slide {
  display: flex;
  justify-content: center;
  align-items: center;

  /*テキストの色と太さを指定*/
  color: #212121;
  font-weight: bold;
  font-size: max(0.5rem, 1.5vw);
}

/*各スライドの背景色の設定*/
.slide1 {
  background-color: #c8e6c9;
}

.slide2 {
  background-color: #80cbc4;
}

.slide3 {
  background-color: #4db6ac;
}
.slide4 {
  background-color: #26a69a;
}

.slide5 {
  background-color: #009688;
}

.slide6 {
  background-color: #00897b;
}

/*サムネイルのスタイル*/
.swiper-thumbnail {
  height: 50px;
}

.swiper-thumbnail .swiper-slide {
  opacity: 0.2;
  transition: opacity 0.5s;
}

/*アクティブなときのスタイル*/
.swiper-thumbnail .swiper-slide.swiper-slide-thumb-active {
  opacity: 1;
}

/*矢印ボタンの色を変更*/
.swiper-button-next,
.swiper-button-prev {
  color: #212121;
}
//定義する順番に注意
// サムネイル
const swiperThumbnail = new Swiper(".swiper-thumbnail", {
  spaceBetween: 10, //スライド感の余白
  slidesPerView: 3, //一度に表示するスライド枚数
  watchSlidesProgress: true //スライダーの動きにスライドを追従させる
});
// スライダー
const slider = new Swiper(".slider", {
  navigation: {
    nextEl: ".swiper-button-next",
    prevEl: ".swiper-button-prev"
  },
  autoplay: true,
  loop: true,
  thumbs: {
    swiper: swiperThumbnail //連動したいスライダー(swiperThumbnailを指定する)
  }
});

External CSS

  1. https://cdn.jsdelivr.net/npm/swiper@8/swiper-bundle.min.css

External JavaScript

  1. https://cdn.jsdelivr.net/npm/swiper@8/swiper-bundle.min.js