JSFiddle - React, Tailwind, and code Playground

HTML

<form id="myform">
    <input id="firstfield" name="firstfield" value="100" type="text" />
    <input id="secondfield" name="secondfield" value="200" type="text" />
</form>

CSS

#myform input[type="text"] {
    border: 1px solid #DBDAD7;
    box-shadow: 1px 1px 4px #F4F4F4 inset;
    font-size: 14px;
    height: 47px;
    line-height: 46px;
    padding: 0 10px;
    margin: 0;
}

JavaScript

jQuery(document).ready(function() {
    $('#firstfield, #secondfield').on({
        "keydown": function(e) {
            if (e.which == 9) {
                alert("TAB key for " + $(this).attr("id") + " .keydown() called.");
            }
        },
        "keyup": function(e) {
            if (e.which != 9) {
                alert("Handler for " + $(this).attr("id") + " .keyup() called.");
            }
        }
    });
});