Bootstrap - Form cleanup

HTML

<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.2.2/backbone-min.js"></script>

JavaScript

$(document).ready(function () {
    var customer = Backbone.Model.extend({
		defaults: {
			age: 85,
			hairColor: 'black',
			timestamp: new Date()
		}
	});
    
    var person = new customer()
    
    person.set('age', 100)
    
    console.log(person.age)
    
});