<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
table {
width: 100%;
}
td:first-child {
background-color: #32a852;
}
td:nth-child(2) {
background-color: #aaaaaa;
}
td:last-child {
background-color: #5696c7;
width: 60%; /* set width of last column to 60% */
}
</style>
</head>
<body>
<table>
<colgroup>
<col span="1" />
<col span="1" />
<col span="1" />
</colgroup>
<tbody>
<tr>
<td>A</td>
<td>C</td>
<td>C</td>
</tr>
</tbody>
</table>
</body>