Document API around code examples

cc @claviska

CONTRIBUTING.md

@@ -3,3 +3,21 @@
 Before contributing, please review the contributions guidelines at:
 
 [webawesome.com/docs/resources/contributing](https://webawesome.com/docs/resources/contributing)
+
+## Website Architecture
+
+### Code Examples
+
+`/docs/_utils/code-examples.js` is a small 11ty plugin that turns the code examples into previews. It relies on a client-side script of the same name that lives in /docs/assets/scripts and gets loaded into the site’s template.
+
+That takes care of rendering standard code blocks. It supports certain modifier classes:
+- `example`: opts a code snippet in to live demo rendering
+- `no-edit`: removes the codepen button
+- `open`: shows the code snippet by default
+
+Modifier classes are used like this:
+```
+```html {.example .no-edit .open}
+```
+
+That will render an example without the CodePen button and with the code already shown.