Regex Numeric (Change Comma Color)
HTML
<div>1,564,23</div>
CSS
div {color: red; font-size: 16px; padding: 10px; }
.digit{ background: #ddd; margin:0 2px; padding: 5px; display: inline-block; color: #000 }
JavaScript
div = $('div');
//div.html(div.text().replace(/,/g, '<span class="comma">$&</span>'));
div.html(div.text().replace(/[0-9]/g, '<span class="digit">$&</span>'));