accordion-group.html

<div role="tab" id="{{::headingId}}" aria-selected="{{isOpen}}" class="panel-heading" ng-keypress="toggleOpen($event)">
  <h4 class="panel-title">
    <a role="button" data-toggle="collapse" href aria-expanded="{{isOpen}}" aria-controls="{{::panelId}}" tabindex="0" class="accordion-toggle" ng-click="toggleOpen()" uib-accordion-transclude="heading" ng-disabled="isDisabled" uib-tabindex-toggle><span uib-accordion-header ng-class="{'text-muted': isDisabled}">{{heading}}</span></a>
  </h4>
</div>
<div id="{{::panelId}}" aria-labelledby="{{::headingId}}" aria-hidden="{{!isOpen}}" role="tabpanel" class="panel-collapse collapse" uib-collapse="!isOpen">
  <div class="panel-body" ng-transclude></div>
</div>