title: UIB Modal Backdrop Not Fading In
body: <p>I am using an angular-ui Modal. When I close the modal, the modal box fades out and up and the backdrop fades out. This is desired behavior.</p>
  
  <p>However when I open the modal, although the modal box fades in and down, the backdrop just appears without fading in. I can't determine why. </p>
  
  <p>This is the code to open the modal:</p>
  
  <pre><code>$scope.update_onclick = function() {
  
      $rootScope.modalInstance = $uibModal.open({
          templateUrl: 'webapp/packagetracker/update.html',
          controller: 'PackageTrackerController',
          backdrop: 'static'        
      });
  
  };
  </code></pre>
  
  <p>This is the backdrop DIV from Chrome's developer tools when the modal is open</p>
  
  <pre><code>&lt;div uib-modal-backdrop="modal-backdrop" class="modal-backdrop fade ng-scope in" ng-style="{'z-index': 1040 + (index &amp;amp;&amp;amp; 1 || 0) + index*10}" uib-modal-animation-class="fade" modal-in-class="in" modal-animation="true" data-bootstrap-modal-aria-hidden-count="1" aria-hidden="true" style="z-index: 1040;"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>I'm using angularjs 1.4.8, angular-animate 1.4.8 and ui-bootstrap-tpls-2.5.0.
  The script tags to add these files are in that order.</p>
  
  <p>Any help would be appreciated. </p>