Display thank you message without reloading on source code embedded form

I have just put the source code on my page. The javascript conflicts on my website so I need to do my own.

Is there a way to take over the form submission like the following which is more efficient? I am making the action go to the iframe so that the page does not have to reload. Is there a better way to handle the form on the page?

<iframe src="" id="contestframe"name="contestframe"></iframe>

<form class="jotform-form" action="https://submit.jotform.us/submit/70804068597162/" method="post" name="form_70804068597162" id="70804068597162" accept-charset="utf-8" target="contestframe"  onDISABLEDsubmit="contestSubmit();return false; "> 

function contestSubmit() {

    if($('#input_3').val() == ''){

      ga('send', 'event', 'SVS Popup', 'Click', 'Please fill in Email Address');

      alert('Please enter your email address');

    }

    else {

      jQuery('.modal-top').css("display","none");

      jQuery('.modal-bottom').css("display","none");

      jQuery('.thanks').css("display","block");

      ga('send', 'event', 'SVS Popup', 'Click', 'Submission');

      $( ".jotform-form" ).submit();

    }

    return false;

  }

I understand that you want to display the thank you page without reloading the page. As I tried to submit the form on the web page provided, I see that thank you message is displaying without any issue. However, you may take a look at the following thread with a similar issue with a solution that might help you.

https://www.jotform.com/answers/1000462-

Let us know if you need any further assistance. We will be happy to assist.