JSFiddle - React, Tailwind, and code Playground

HTML

<table>
<tr class="evenPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="oddPack">
</tr>
<tr class="oddSubPack">
</tr>
<tr class="oddSubPack">
</tr>
<tr class="oddSubPack">
</tr>
<tr class="oddSubPack">
</tr>
<tr class="evenPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="evenSubPack">
</tr>
<tr class="evenSubPack">
</tr>
   </table>

JavaScript

$("tr").html("hi");
    $("tr").click(function() {
        var active =  $(this).attr("class").indexOf('even') > -1 ? 'odd' : 'even';
        $(this).nextUntil('.' + active + 'Pack').slideToggle();
    });