<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $('#hideshow').on('click', function(event) {
     $('.content').toggle('show');
  });
});
</script>
<div class="content" style="border:0;display:none">[Form id="1"]</div>
<button id='hideshow'>Inscription</button>