JSFiddle - React, Tailwind, and code Playground

HTML

<table id="theTab">
    <tr><td>row 1</td></tr>
    <tr class="hidden"><td>row 2</td></tr>
    <tr><td>row 3</td></tr>
    <tr><td>row 4</td></tr>
    <tr class="hidden"><td>row 5</td></tr>
    <tr><td>row 6</td></tr>
</table>

CSS

table tr.hidden{
    display: none;
}

table tr.odd {
   background-color: #F40
}

table tr.even {
   background-color: #4F0
}

JavaScript

var classToggle = false;

$("#theTab tr:not(.hidden)").each(function(){
    $(this).addClass(classToggle ? "odd" : "even");
    classToggle = !classToggle;
});