ブラー溶け込み遷移

<div class="d08-04-07-stage">
          <div class="d08-04-07-page d08-04-07-a">
            <strong>ギャラリー</strong>
            <p>作品一覧</p>
          </div>
          <div class="d08-04-07-page d08-04-07-b">
            <strong>作品詳細</strong>
            <p>拡大表示</p>
          </div>
          <button type="button" class="d08-04-07-btn">開く</button>
        </div>

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