fix styles to allow for valid table markup variations

Created by: tinyfly

The baseline table styles are a bit messed up if you have multiple <tbody>s a <tfoot> and <th>s in either of those. This is all perfectly valid markup. This commit fixes the styling in those cases.

Here is some example table markup:

<table>
    <thead>
        <tr scope="col">column heading</tr>
        <tr scope="col">column heading</tr>
        <tr scope="col">column heading</tr>
    </thead>

    <tfoot>
        <tr>
            <th scope="row" colspan="2">Row heading</th>
            <td>data</td>
        </tr>
    </tfoot>

    <tbody>
        <tr>
            <th scope="row">Row heading</th>
            <td>data</td>
            <td>data</td>
        </tr>
        <tr>
            <th scope="row">Row heading</th>
            <td>data</td>
            <td>data</td>
        </tr>
    </tbody>

    <tbody>
        <tr>
            <th scope="row">Row heading</th>
            <td>data</td>
            <td>data</td>
        </tr>
        <tr>
            <th scope="row">Row heading</th>
            <td>data</td>
            <td>data</td>
        </tr>
    <tbody>
</table>