<div ng-controller="SimpleTestController as simpleCtrl">
  <button type="button" class="btn btn-primary" ng-click="simpleCtrl.isBlue = !simpleCtrl.isBlue">Toggle Simple Color</button>

  <bb-simple bb-simple-is-blue="simpleCtrl.isBlue">
    <div style="width: 200px; height: 200px">
       <h2 style="color: white">Simple Content</h2>
    </div>
  </bb-simple>
</div>