透過→白ヘッダー

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          <header class="d03-01-06-header">
            <span class="d03-01-06-logo">BRAND</span>
            <nav class="d03-01-06-nav">
              <a href="#" onclick="return false">サービス</a>
              <a href="#" onclick="return false">実績</a>
              <a href="#" onclick="return false">お問い合わせ</a>
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          </header>
          <div class="d03-01-06-scroll">
            <div class="d03-01-06-hero">
              <p>↓ スクロールでヘッダーが白に</p>
            </div>
            <div class="d03-01-06-content">
              <div class="d03-01-06-block"></div>
              <div class="d03-01-06-block"></div>
              <div class="d03-01-06-block"></div>
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