How to do nested multiple checkbox with awesome-bootstrap-checkbox library?

Trying to do nested multiple checkbox under radio button with awesome-bootstrap-checkbox but nested input elements get parent radio button style.

<div class="radio">
    <input type="radio" name="radio1" id="parent-slot-1" value="true">
    <label for="parent-slot-1">
        Radio label
    </label>
        <div class="checkbox">
            <input type="checkbox"  class="styled" id="child-slot-1">
            <label for="child-slot-1">
               Child label
            </label>
        </div>

    <div class="checkbox">
            <input type="checkbox"  class="styled" id="child-slot-2">
            <label for="child-slot-2">
               Child label
            </label>
        </div>
  </div>

This is my codepen example http://ift.tt/2baIEeg

P.S. I need that it will be nested because it's part of Angular application and list is created dynamically by ng-repeat.