<!doctype html>
<html>
  <head>
    <meta charset="utf-8" />
  </head>
  <script>
    const { pathname } = window.location;
    const match = pathname.match('^/_/[^/]+');
    const baseUrl = match ? `${match[0]}/` : '/';
  </script>
  <body></body>
</html>
