Bootstrap 3 - Form inside modal

HTML

<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.css">
<link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/font-awesome/4.1.0/css/font-awesome.min.css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
<form id="myForm">
    Number of Messages: <input id="msgs" type="text"> </input>
    <div id="addmsg">
    </div>
</form>

JavaScript

$("#msgs").on('change', function()
{
	var num = this.value;
    if(Math.floor(num) == num && $.isNumeric(num))
    {
         $("#addmsg").text('');
        for(var i = 0; i < num; i++)
        {
            $("#addmsg").append("<input type='text'/><br/>");
        }
    }
});