<link href="https://cdn.jsdelivr.net/npm/select2@4.1.0-rc.0/dist/css/select2.min.css" rel="stylesheet" />

<script src="https://cdn.jsdelivr.net/npm/select2@4.1.0-rc.0/dist/js/select2.min.js"></script>

<script type="text/javascript">
	$(document).ready(function() {
		$('.sel2').select2({
			dropdownParent: $('#popupForm')
		});
	});
</script>

<style type="text/css">
		.select2-selection__rendered {
			line-height: 40px !important;
			font-size:16px !important;
			color:#666666 !important;
		}
		.select2-selection {
			height: 40px !important;
			font-size:16px !important;
			color:#666666 !important;
		}
</style> 