JSFiddle - React, Tailwind, and code Playground
HTML
<div class="box" style="color:blue;">div 0</div>
<div class="box" style="color:blue;">div 1</div>
<div class="box">div 2</div>
JavaScript
$('.box').each(function(i){
var color = $(this).css('color');
if (color == 'rgb(0, 0, 255)' || color == 'blue') //=='blue' <- IE hack
alert("div " + i + " is blue!\nColor detected: " + color);
});