```
% pandoc -t revealjs --slide-level=3
# One

One

## Two

Two

### Three

Three

#### Four

Four
^D
<section id="one" class="title-slide slide level1">
<h1>One</h1>
<p>One</p>
</section>
<section>
<section id="two" class="title-slide slide level2">
<h2>Two</h2>
<p>Two</p>
</section>
<section id="three" class="slide level3">
<h3>Three</h3>
<p>Three</p>
<h4 id="four">Four</h4>
<p>Four</p>
</section>
</section>
```