JSFiddle - React, Tailwind, and code Playground

HTML

<table>
<thead>
 <tr>
   <th colspan="2">col1</th>
   <th rowspan="2">col2</th>
   <th rowspan="3">col3</th>
 </tr>
 <tr>
   <th>col4</th>
 </tr>
 <tr>
   <th colspan="2">col5</th>
   <th>col7</th>
 </tr>
     </thead>
        <tbody>
 <tr>
   <td>value</td>
   <td>value1</td>
   <td>value2</td>
   <td>value3</td>
 </tr>
</tbody>
</table>

CSS

table, th, td {
  border: 1px solid;
}