Всплывающее окно без jQuery плагинов

<script src="index.js"></script>
<link rel="stylesheet" href="css.css">

<script>const modal = new VanillaModal()</script>

<a href="#modal-1" rel="modal:open">One Prodigious Cat</a>

<div id="modal-1" style="display:none">
  Lorem ipsum dolor sit amet, consectetur adipisicing elit. Ipsam itaque aperiam porro temporibus saepe pariatur ad, asperiores cumque recusandae provident aliquam nulla, ex, explicabo eos suscipit culpa sapiente nesciunt quas!
</div>

<div class="modal">
  <div class="modal-inner">
	<a rel="modal:close">&times;</a>
	<div class="modal-content" id="modal-1">33</div>
  </div>
</div>