Extension: Code
The code extension contains default styles for displaying code and related elements in HTML.
You'll find it in src/extensions/_code.scss.
Monospace
The code extension makes sure appropriate elements—such as
<code><pre><kbd><samp>
This is handy whenever a font-stack
has been explicitly applied to the <body> (which overrides the browser defaults).
For example, Level 4 sets an explicit font stack,
and its demo page has this code extension included.