show Modal:
----------------------------
$('#modal_id').modal('show');
hide and show Modal (toggle):
-----------------------------
$('#modal_id').toggle('modal');
<!-- Modal HTML embedded directly into document -->
<div id="ex1" class="modal">
<p>Thanks for clicking. That felt good.</p>
<a href="#" rel="modal:close">Close</a>
</div>
<!-- Link to open the modal -->
<p><a href="#ex1" rel="modal:open">Open Modal</a></p>