JSFiddle - React, Tailwind, and code Playground
HTML
<table id="tblSample" border="1" cellpadding="0" cellspacing="0" width="300px">
<tr>
<td>1</td>
<td>1</td>
</tr>
<tr>
<td>2</td>
<td>2</td>
</tr>
</table>
<table id="tblSample2" border="1" cellpadding="0" cellspacing="0" width="300px">
<tr>
<td>1</td>
<td>1</td>
</tr>
<tr>
<td>2</td>
<td>2</td>
</tr>
</table>
JavaScript
$("#tblSample > tbody > tr").css("background-color", "gray");
$("#tblSample2 tr").css("background-color", "gray");