How can I change the border color of this. I generally got it from this answer
$(document).ready(function() {
$("select").select2();
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<link href="https://cdn.jsdelivr.net/npm/select2@4.0.13/dist/css/select2.min.css" rel="stylesheet" />
<script src="https://cdn.jsdelivr.net/npm/select2@4.0.13/dist/js/select2.min.js"></script>
<select id="select_page" style="width:200px;" class="operator" style="border: 2px solid red;">
<option value="">Select a Page...</option>
<option value="alpha">alpha</option>
<option value="beta">beta</option>
<option value="theta">theta</option>
<option value="omega">omega</option>
</select>