I would appreciate any help. I have set a contact form up and want to show a button to download a file once the form is submitted. This is showing all the time and should be hidden until the form is filled in.

 <div class="visible-only-if-sent"> 
  <a href="demo.ogi.co.uk/download/1323" class="button big_large_full_width center default">Download CVM10-Lite
  </a> 
 </div>

But it is still showing on the page all the time. Can you please help me if I’m doing something wrong somewhere?