The generated topic files must be structured as follows:
<article class="doc">
<!-- Topic title -->
<h1>Topic Title</h1>
<!-- Topic content -->
<div id="preamble">
[...]
</div>
<!-- Child topic -->
<div class="sect1">
<!-- Child topic title -->
<h2 id="_child_1"><a class="anchor" href="#_child_1"></a>Level 1 subtopic</h2>
<!-- Topic content -->
<div class="sectionbody">
[...]
</div>
<!-- Grandchild topic -->
<div class="sect2">
<!-- Grandchild topic title -->
<h2 id="_child_11"><a class="anchor" href="#_child_11"></a>Level 2 subtopic</h2>
<!-- Grandchild topic content -->
<div class="sectionbody">
[...]
</div>
</div>
</div>
</article>