JSFiddle - React, Tailwind, and code Playground

HTML

<div style="background-color: white;" >
    &nbsp;
</div>
<div style="background-color: #ffffff;"  >
    &nbsp;
</div>
<div style="background-color: #FFFFFF;"  >
    &nbsp;
</div>
<div style="background-color: rgb(255,255,255);"  >
    &nbsp;
</div>

JavaScript

$('div').each(function() {
    alert($(this).css('background-color') == 'rgb(255, 255, 255)');
});