It's not a public domain book, so I'm sure how much I can upload without issues. And without the entire book, just a sample of it most likely won't have an instance of where the number falls on one page and the text on another, it of course doesn't happen everytime there's a section number. But here's the code for a section including the title, if this will help at all:
Spoiler:
<body class="calibre">
<p class="calibre7"><span class="calibre11"><span class="bold1">X</span></span></p>
<div class="calibre6">
</div>
<p class="calibre7"><span class="calibre11"><span class="bold1">X</span></span></p>
<div class="calibre6">
</div>
<p class="calibre10"><span class="calibre8"><span class="bold1"><span class="calibre11">F</span></span>irst paragraph after new section to keep connected to the above number.</span></p>
</body>
</html>
And from the stylesheet: