<!DOCTYPE html>
<table style="width: 300px" cellspacing="0" cellpadding="0">
    <td style="background: yellow;">
        <div style="width: 20px; height: 150px;"></div>
    </td>
    <td style="background: green;">
        <div style="width: 40px; height: 150px;"></div>
    </td>
</table>