JSFiddle - React, Tailwind, and code Playground

HTML

<table id="hours">
 <tbody>
    <tr class="test2">
        <td><input type="checkbox" id="start"></input></td>
        <td>hi</td>
     </tr>
     <tr class="test3">
        <td><input type="checkbox" id="start"></input></td>
        <td>again</td>
     </tr>
</tbody>
</table>

CSS

table {
background: blue;
}
#start:checked  ~ table {
    background: red;
}