Barve ozadja stolpcev

<table>
<colgroup style="background-color:red">
<col /><col style="background-color:green" />
<col /><col />
<colgroup>
   <tr>
	<td>Nedelja</td>
	<td>Ponedeljek</td>
	<td>Torek</td>
	<td>Sreda</td>
	<td>četrtek</td>
	<td>Petek</td>
	<td>Sobota</td>
   </tr>
   <tr>
    ...     ...
   </tr>
   <tr>
	<td>3</td>
	<td>4</td>
	<td>5</td>
	<td>6</td>
	<td>7</td>
	<td>8</td>
	<td>9</td>
   </tr>
</table>