page.html

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    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <meta name="color-scheme" content="light dark" />
    <title>A relative link</title>
    <meta property="og:title" content="A relative link" />
    <meta property="og:type" content="website" />
    <meta name="twitter:card" content="summary" />
    <style>
      /* Pagez's theme.css */
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    <main>
<p>The <a href="./data.csv">data</a> behind this page, and <a href="./other/">another page</a>.</p>
</main>
  </body>
</html>