メガメニュー(3カラム+おすすめ枠)

<nav class="d03-02-12-nav">
          <div class="d03-02-12-top"><a href="#" class="d03-02-12-trig">サービス一覧 ▾</a></div>
          <div class="d03-02-12-mega">
            <div class="d03-02-12-col">
              <p class="d03-02-12-h">制作</p>
              <a href="#">コーポレートサイト</a><a href="#">ランディングページ</a><a href="#">ECサイト</a>
            </div>
            <div class="d03-02-12-col">
              <p class="d03-02-12-h">運用</p>
              <a href="#">保守・更新</a><a href="#">SEO対策</a><a href="#">広告運用</a>
            </div>
            <div class="d03-02-12-feat">
              <p class="d03-02-12-fh">おすすめ</p>
              <p class="d03-02-12-ft">春の制作キャンペーン実施中</p>
              <a href="#" class="d03-02-12-fbtn">詳しく見る</a>
            </div>
          </div>
        </nav>

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        .d03-02-12-trig{display:inline-block;padding:10px 16px;background:#eef2ff;color:#1f2937;font-weight:600;text-decoration:none;border-radius:8px}
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        .d03-02-12-nav:hover .d03-02-12-mega{opacity:1;visibility:visible;transform:translateY(0)}
        .d03-02-12-col{display:flex;flex-direction:column;gap:8px}
        .d03-02-12-h{margin:0 0 2px;font-size:11px;color:#94a3b8;font-weight:700;letter-spacing:.03em}
        .d03-02-12-col a{color:#374151;text-decoration:none;font-size:12.5px}
        .d03-02-12-col a:hover{color:#4f46e5}
        .d03-02-12-feat{flex:0 0 110px;background:linear-gradient(135deg,#4f46e5,#7c3aed);border-radius:10px;padding:12px;color:#fff;display:flex;flex-direction:column;gap:6px}
        .d03-02-12-fh{margin:0;font-size:10px;font-weight:700;opacity:.85}
        .d03-02-12-ft{margin:0;font-size:11.5px;line-height:1.5}
        .d03-02-12-fbtn{margin-top:auto;font-size:11px;font-weight:700;color:#fff;text-decoration:underline}