タブ切り替え型メガメニュー(1タブ表示状態)

<div class="d03-12-05-stage">
          <div class="d03-12-05-tabs">
            <span>会社情報</span>
            <span class="active">料金プラン</span>
            <span>サポート</span>
          </div>
          <div class="d03-12-05-panel">
            <div class="d03-12-05-plan">
              <strong>ライト</strong>
              <span class="price">¥980<em>/月</em></span>
              <span class="desc">個人・小規模向け</span>
            </div>
            <div class="d03-12-05-plan d03-12-05-plan-hi">
              <span class="d03-12-05-tag">人気</span>
              <strong>スタンダード</strong>
              <span class="price">¥2,980<em>/月</em></span>
              <span class="desc">チーム利用に最適</span>
            </div>
            <div class="d03-12-05-plan">
              <strong>プレミアム</strong>
              <span class="price">¥5,980<em>/月</em></span>
              <span class="desc">大規模組織向け</span>
            </div>
          </div>
        </div>

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