Angular ui modal form not displaying form

For studying angular js, I created an angular application for performing CRUD operation. I wanted to add modal form on my application. So when user click to add an item a modal form popups. For that I used angular ui of bootstrap. I tried to use the code http://plnkr.co/edit/dRahuG?p=preview which is in the ui bootstrap tutorial. It working fine in the plunker but not in application.

<div class="container" ng-controller="ClassController">
    <script type="text/ng-template" id="myModalContent.html">
        <div class="modal-header">
            <h3>I'm a modal!</h3>
        </div>
        <form ng-submit="submit()">
          <div class="modal-body">
            <label>User name</label>
            <input type="text" ng-model="user.user" />
            <label>Password</label>
            <input type="password" ng-model="user.password" />
          </div>
          <div class="modal-footer">
              <button class="btn btn-warning" ng-click="cancel()">Cancel</button>
              <input type="submit" class="btn primary-btn" value="Submit" />
          </div>
        </form>
    </script>
    <button class="btn" ng-click="open()">Add</button>
    <div ng-show="selected">aSelection from a modal: {{ selected }}</div>
</div>

And my controller is

var myApp = angular.module('myApp', ['ui.bootstrap']);
myApp.controller('ClassController',['$scope','$http','$modal','classFactory',function($scope,$http,$modal){

      $scope.items = ['item1', 'item2', 'item3'];

    $scope.open = function () {

        $modal.open({
            templateUrl: 'myModalContent.html',
            backdrop: true,
            windowClass: 'modal',
            controller: function ($scope, $modalInstance) {

                $scope.submit = function () {

                    $modalInstance.dismiss('cancel');
                }
                $scope.cancel = function () {
                    $modalInstance.dismiss('cancel');
                };
            },
            resolve: {
                items: function () {
                    return $scope.items;
                }
            }
        });
    };

}])

When I clicked the button the screen get darken but the modal form is not coming. I don't know where I gone wrong. I am using sails.js to load the server. Moreover I am beginner in angular js.