I have the following code, how could I make the table borders radius if borders are collapsed?
<table>
<thead>
<tr>
<th colspan="2">Head</th>
</tr>
</thead>
<tbody>
<tr>
<td>b1</td>
<td>b2</td>
</tr>
<tr>
<td>b3</td>
<td>b4</td>
</tr>
</tbody>
</table>