Adding support for your own languages is very easy, however, and theming is done entirely with CSS. If you don’t want to sweat the details of theming, you can use one of their many built-in themes (like the very popular solarized theme).
Getting started is easy:
<pre><code data-language="ruby">def greeting(name) puts "Hello there #(name)" end</code></pre>
Then include your CSS theme in the
<head> and rainbow.js (as well as whichever language[s] you want) before the closing