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>
 
    