Minimal pure CSS Treeview with FontAwesome expanders

Update 2015-07-18: shux! not valid to apply ::before/after psuedo elements to <input> since it's not technically content (stack-o reference)

jQuery replacement:

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Works in Chrome and Safari but not Firefox or IE :(

Look ma, no JavaScript! :)

Leveraging (hidden) checkbox element to maintain expand/collapse state and

:before {content: "xyz" }

 css to avoid extra elements.
Not an original idea but wanted to see of i could trim down all the extra html markup & css required.
Turned out swell! The <input> is the only additional overhead above standard markup, sahweet!