JSFiddle - React, Tailwind, and code Playground

by AnthraxisBR

HTML

<div class='div' style='background-color:#000' id='1'>

</div>
<div class='div' style='background-color:#999' id='2'>

</div>
<div class='div' style='background-color:#888' id='3'>

</div>

JavaScript

var divs = $('.div');
divs.each(function(a) {
  var rgb = $(this).css("background-color");
  var hex = hexc(rgb);
  if (hex == '#000000') {
    alert($(this).attr('id'));
  }
});

// FONTE -> https://stackoverflow.com/questions/15716702/get-background-color-in-000-format-and-not-rgb
function hexc(colorval) {
  var parts = colorval.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
  delete(parts[0]);
  for (var i = 1; i <= 3; ++i) {
    parts[i] = parseInt(parts[i]).toString(16);
    if (parts[i].length == 1) parts[i] = '0' + parts[i];
  }
  color = '#' + parts.join('');
  return color;
}