<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div id="PersianGulf-Modal" class="modal fade" role="dialog">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-body">
<p class="text-left-side">
<b>PersianGulf forever...</b><br><br>
</p>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-default" data-dismiss="modal"><b>Agree!<b></button>
</div>
</div>
</div>
</div>
the Modal runs 1 time in every session.<br/>
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