Jquery number count animation

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  sample: false,
  actions: {
   aa(){
   	this.toggleProperty("sample");
     
        $('.count').prop('Counter', 20).animate(
          {
            Counter: $('.count').text()
        	}, {
            duration: 2000,
            easing: 'swing',
            step: function (now) {
                $(this).text(Math.ceil(now));
            }
        });
    
   } 
  }
});

templates.application.hbs

<h1 {{action "aa" }}>Welcome to {{appName}}</h1>
{{#liquid-bind sample}}
sample
{{/liquid-bind}}
{{velocity-bind}}
<br>
<br>
<div id="shiva"><span class="count">200</span></div>
{{outlet}}
<br>
<br>

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2",
    "liquid-fire": "0.28.0"
  }
}