Empty AngularJS 1.4.8

Empy fiddle for AngularJS

HTML

<div ng-app="myApp">
  <div ng-controller="MyCtrl">
    <div ng-repeat="i in items">
      <div ng-repeat="j in i" ng-class='{active: $first && $parent.$first}'>
        {{j}}
      </div>
    </div>
  </div>
</div>

CSS

.active {
  background-color: red;
}

JavaScript

var myApp = angular.module('myApp', []);
myApp.controller('MyCtrl', ['$scope', function($scope) {
  $scope.items = [
    [1, 2],
    [3, 4]
  ];
}]);