syntax highlighting and some clarity

docs/guides/setup.md

@@ -86,11 +86,17 @@ The second argument is an options object. It allows you to set additional option
 
 The third argument is a 'ready' callback. Once Video.js has initialized it will call this function.
 
+Instead of using an element ID, you can also pass a reference to the element itself.
+
+```js
 videojs(document.getElementsById('example_video_1')), {}, function()) {
   // This is functionally the same as the previous example.
 });
+```
 
+```js
 videojs(document.getElementsByClassName('awesome_video_class')[0], {}, function()) {
   // You can grab an element by class if you'd like, just make sure
   // if it's an array that you pick one (here we chose the first).
 });
+```