JSFiddle - React, Tailwind, and code Playground

HTML

<table>
    <th>
        timestamp
    </th>
    <th>
        source 1
    </th>
    <th>
        source 2
    </th>
    <th>
        source 3
    </th>
    <tr>
        <td>
            timestamp 1
        </td>
        <td>
            source 1 value 1
        </td>
    </tr>
    <tr>
        <td>
            timestamp 2
        </td>
        <td>
            source 1 value 2
        </td>
    </tr>
    <tr>
        <td>
            timestamp 3
        </td>
        <td>
            source 1 value 3
        </td>
    </tr>
    <tr>
        <td>
            timestamp 1
        </td>
        <td>
        </td>
        <td>
            source 2 value 1
        </td>
    </tr>
    <tr>
        <td>
            timestamp 2
        </td>
        <td>
        </td>
        <td>
            source 2 value 2
        </td>
    </tr>
    <tr>
        <td>
            timestamp 3
        </td>
        <td>
        </td>
        <td>
            source 2 value 3
        </td>
    </tr>
    <tr>
        <td>
            timestamp 1
        </td>
        <td>
        </td>
        <td></td>
        <td>
            source 3 value 1
        </td>
    </tr>
    <tr>
        <td>
            timestamp 2
        </td>
        <td>
        </td>
        <td></td>
        <td>
            source 3 value 2
        </td>
    </tr>
    <tr>
        <td>
            timestamp 3
        </td>
        <td>
        </td>
        <td></td>
        <td>
            source 3 value 3
        </td>
    </tr>
</table>

CSS

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