JSFiddle - React, Tailwind, and code Playground
HTML
<select id="selection">
<option>foo</option>
<option>bar</option>
<option>fizz</option>
<option>buzz</option>
</select>
JavaScript
$( document ).ready(function() {
//This highlights the select, but also all the items in it
//$("#selection").css("background-color", "pink");
//You can only see the highlight when you click on the select
$("#selection option:selected").css("background-color", "pink");
});