JSでTabコンテンツ作成

<section class="tab_section">
        <div class="section_inner">
          <h2 class="section_title">タブコンテンツの作り方</h2>
          <p class="scrool_text mobile-only">横スクロールできます</p>
          <div class="tab-container">
            <div class="tab-buttons">
              <button class="tab-btn active">タブ1タブ1</button>
              <button class="tab-btn">タブ2タブ2タブ2</button>
              <button class="tab-btn">タブ3</button>
              <button class="tab-btn">タブ4タブ4</button>
              <button class="tab-btn">タブ5</button>
              <button class="tab-btn">タブ6タブ6タブ6</button>
            </div>
            <div class="tab-contents">
              <div class="tab-content active">タブ1の内容</div>
              <div class="tab-content">タブ2の内容</div>
              <div class="tab-content">タブ3の内容</div>
              <div class="tab-content">タブ4の内容</div>
              <div class="tab-content">タブ5の内容</div>
              <div class="tab-content">タブ6の内容</div>
            </div>
          </div>
        </div>
      </section>

@charset "utf-8";

/*---------------tabの設定-------------------------------*/

/* タブセクション全体のスタイル */

.tab_section {
  width: 100%;
  margin-block: 100px;
  /* 必要に応じてmin-heightを調整 */
}
.section_inner {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
}
.section_title {
  position: relative;
  font-size: min(2.78vw, 40px);
  font-weight: bold;
  color: var(--text-color);
  text-align: left;
  margin-bottom: min(1.39vw, 20px);
  padding-left: 15px;
}
.section_title::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 5px;
  height: 100%;
  background-color: var(--black--);
}
h3 {
  font-size: min(1.3888888888888888vw, 20px);
  font-weight: bold;
  color: var(--text-color);
  text-align: left;
  margin-block: 20px;
  padding-left: 15px;
}

/* スクロール案内テキスト */
.scrool_text {
  font-size: 12px;
  margin-top: 8px;
  margin-bottom: 12px;
  padding-right: 10px;
  color: #555;
  text-align: right;
}
.scrool_text::after {
  content: "→";
  font-size: 20px;
  display: inline-block;
  margin-left: 5px;
  animation: scrollArrow 0.8s infinite alternate;
}
@keyframes scrollArrow {
  0% {
    opacity: 1;
    transform: translateX(0);
  }
  100% {
    opacity: 1;
    transform: translateX(5px);
  }
}

/*---------------タブ全体の設定--------------------*/

.tab-container {
  width: 100%;
  margin: 40px auto;
  background: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  padding: 24px;
}
.tab-buttons {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}
.tab-btn {
  /*幅を指定したい時はmin-widthかmax-widthを使用*/
  flex: 1;
  padding: 12px 0;
  background: #f5f5f5;
  border: none;
  border-radius: 4px 4px 0 0;
  font-size: min(1.1111111111111112vw, 16px);
  font-weight: bold;
  cursor: pointer;
  transition: background 0.2s;
}
.tab-btn.active {
  background: #4285f4;
  color: #fff;
}
.tab-content {
  display: none;
  padding: 24px 8px;
  border-top: 1px solid #e0e0e0;
  font-size: min(1.1111111111111112vw, 16px);
}
.tab-content.active {
  display: block;
}

@media screen and (max-width: 768px) {
  .tab-container {
    margin: 20px auto;
  }
  .tab-buttons {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
    overflow-x: auto;
    white-space: nowrap;
    scrollbar-width: thin; /* Firefox用 */
  }
  .tab-btn {
    min-width: 140px;
    padding: 12px 10px;
    background: #f5f5f5;
    border: none;
    border-radius: 4px 4px 0 0;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.2s;
    white-space: nowrap;
    font-size: min(2.083333333333333vw, 16px);
  }
  .tab-content {
    font-size: min(2.083333333333333vw, 16px);
  }
}

@media screen and (max-width: 450px) {
  .tab-btn {
    min-width: 140px;
    padding: 12px 10px;
    font-size: min(3.111111111111111vw, 14px);
  }
  .tab-content {
    font-size: min(2.666666666666667vw, 12px);
  }
}

// タブ切り替え処理
document.addEventListener("DOMContentLoaded", function () {
  const tabBtns = document.querySelectorAll(".tab-btn");
  const tabContents = document.querySelectorAll(".tab-content");
  tabBtns.forEach((btn, idx) => {
    btn.addEventListener("click", function () {
      tabBtns.forEach((b) => b.classList.remove("active"));
      tabContents.forEach((c) => c.classList.remove("active"));
      btn.classList.add("active");
      tabContents[idx].classList.add("active");
    });
  });
});