JSFiddle - React, Tailwind, and code Playground
HTML
<table>
<thead>
<tr>
<th>H1</th>
<th>H2</th>
<th>H3</th>
</tr>
</thead>
<tbody>
<tr>
<td>C1</td>
<td>C2</td>
<td>C3</td>
</tr>
<tr>
<td>C1</td>
<td>C2</td>
<td>C3</td>
</tr>
</tbody>
</table>
CSS
table{
width:100%
}
JavaScript
$("td, th").css("border-right","1px solid black");