背景ブラーで開くオーバーレイメニュー

<div class="d03-08-07-frame">
          <div class="d03-08-07-bar">
            <span class="d03-08-07-logo">Gallery</span>
            <button class="d03-08-07-burger" type="button" aria-label="メニューを開く" aria-expanded="false">
              <span></span><span></span><span></span>
            </button>
          </div>
          <div class="d03-08-07-body">
            <div class="d03-08-07-ph"></div>
            <div class="d03-08-07-ph"></div>
            <div class="d03-08-07-ph"></div>
          </div>
          <div class="d03-08-07-overlay">
            <a href="#">作品一覧</a>
            <a href="#">展示予定</a>
            <a href="#">アクセス</a>
            <a href="#">お問い合わせ</a>
          </div>
        </div>

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        .d03-08-07-overlay a{color:#1e293b;text-decoration:none;font-size:14px;font-weight:700}
        .d03-08-07-overlay a:hover{color:#4f46e5}

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