How to modify the class on POPTP_TPL?

ionic-v1
1

I want modify the alert class not the button class,I want modify the alert class according to ‘ng-class’,how to do it?

var POPUP_TPL = ‘<div class=“popup” ng-class=“mine”>’ +
’<div class=“popup-head”>’ +
’<h3 class=“popup-title” ng-bind-html=“title”></h3>’ +
’<h5 class=“popup-sub-title” ng-bind-html=“subTitle” ng-if=“subTitle”></h5>’ +
’</div>’ +
’<div class=“popup-body”>’ +
’</div>’ +
’<div class=“popup-buttons row”>’ +
’<button ng-repeat=“button in buttons” ng-click="$buttonTapped(button, $event)" class="button col"
ng-class="button.type || ‘button-default’"
ng-bind-html=“button.text”></button>’ +
’</div>’ + ‘</div>’;

2 
    $ionicPopup.show({
  template: "<style>.popup { width:500px; }</style><p>That's the popup content<p/>",
  title: 'MyTitle',
  subTitle: 'MySubTitle',
  scope: $scope,
  buttons: [
   { text: 'Annuler' },
   {
     text: '<b>Save</b>',
     type: 'button-positive',
     onTap: function() { console.log('...') }
   }
  ]
});