Unfortunately, this particular request is beyond the scope of support and is not a theme related issue. You might need to find a plugin which I doubt if available or hire a freelance developer to add the feature for you. Please visit Envato Studio or Werkpress for further customization. You can also vote or post the feature on our Feature Requests page.
If you have any further questions about the theme, we are more than happy to provide you with assistance on these inquiries. Thank you for your understanding.