```
% pandoc --section-divs
# Book Title

::: {#ch1 .section}
## Chapter 1
Hello world.
:::

::: {#ch2 .section}
## Chapter 2
Goodbye world.
:::
^D
<section id="book-title" class="level1">
<h1>Book Title</h1>
<section id="ch1" class="level2">
<h2 id="chapter-1">Chapter 1</h2>
<p>Hello world.</p>
</section>
<section id="ch2" class="level2">
<h2 id="chapter-2">Chapter 2</h2>
<p>Goodbye world.</p>
</section>
</section>
```