<!DOCTYPE html>
<html>
<head>
<style>
table, th, td {
border: 1px solid black;
}
colgroup {
display: table-column-group;
}
</style>
</head>
<body>
<p>Look how the colgroup element is displayed below:</p>
<table>
<colgroup>
<col span="2" style="background-color:red">
<col style="background-color:yellow">
</colgroup>
<tr>
<th>ISBN</th>
<th>Title</th>
<th>Price</th>
</tr>
<tr>
<td>3476896</td>
<td>My first HTML</td>
<td>$53</td>
</tr>
<tr>
<td>5869207</td>
<td>My first CSS</td>
<td>$49</td>
</tr>
</table>
<p>Change the default CSS settings to see the effect.</p>
</body>
</html>