Checkbox input not checking when clicked (CSS toggle switch styling)

I am using a custom CSS toggle switch to style my checkbox inputs. GitHub Project

However, when you click one of the checkbox toggles, it registers the click twice and never changes the checked value. If the checkbox starts off unchecked, it will remain unchecked. If it starts off checked, it will remain checked.

I've made a fiddle demonstrating the issue: http://ift.tt/1QtfJiI

The HTML for the styled checkbox looks like this:

<label class="switch-light switch-candy" onclick="doSomething($(this));">
  <input type="checkbox" />

  <strong>
    Wireless
  </strong>

  <span>
    <span>Off</span>
    <span>On</span>
    <a></a>
  </span>
</label>

This is the CSS file where all the styling is done: http://ift.tt/1T9JpY5