<div class="swiper">
  <div class="swiper-container slider">
    <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 class="swiper-container swiper-thumbnail">
    <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>
</div>

/*コンテナ要素のスタイル*/
.swiper {
  display: flex;
  flex-flow: column nowrap;
  gap: 16px;
  height: 300px;
  width: 100%;
}

.swiper-container {
  overflow: hidden;
  width: 100%;
}

/*各スライドのスタイル*/
.swiper-slide {
  flex-flow: column nowrap;
  /*テキストの位置調整*/
  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;
}

/* スライダーのスタイル */
.slider {
  position: relative;
  width: 100%;
  flex-grow: 1;
}
/* サムネイルのスタイル */
.swiper-thumbnail {
  height: 50px;
}

.swiper-thumbnail .swiper-wrapper {
  flex-direction: row;
}

/*アクティブなときのスタイル*/
.swiper-thumbnail .swiper-slide {
  flex-flow: row nowrap;
  cursor: pointer;
  opacity: 0.2;
  transition: opacity 0.5s;
}
.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;
}

/*PCサイズのスタイル*/
@media (min-width: 599px) {
  .swiper {
    flex-flow: row nowrap;
  }
  .swiper-thumbnail {
    width: 40%;
    height: 100%;
  }
  .swiper-thumbnail .swiper-wrapper {
    flex-direction: column;
  }
  .swiper-thumbnail .swiper-slide {
    flex-flow: column nowrap;
  }
}

const swiperThumbnail = new Swiper(".swiper-thumbnail", {
  spaceBetween: 16,
  slidesPerView: 3,
  centeredSlides: true,
  centeredSlidesBounds: true,
  watchSlidesProgress: true,
  breakpoints: {
    599: {
      direction: "vertical"
    }
  }
});
const slider = new Swiper(".slider", {
  spaceBetween: 16,
  navigation: {
    nextEl: ".swiper-button-next",
    prevEl: ".swiper-button-prev"
  },
  autoplay: true,
  loop: true,
  thumbs: {
    swiper: swiperThumbnail
  }
});