[phossler]

FWIW, I've always found Tables to be tricky so I made my CSS as simple as i could

Sometimes inline CSS and sometimes CSS classes

Here's just my example for both, with

<td style="width: 35%">

the inline and

<td class="second">2</td>

the clsss

Spoiler:

table {
width: 60%;
margin-left: 15%;
margin-right: 15%;
text-align: center;
border: 3px solid black;
border-collapse: collapse;
}

th {
font-style:italic;
height:3em;
vertical-align: middle;
padding:5px;
border-bottom: 3px solid black;
}

tr {
margin-top:1em;
margin-bottom: 1em;
height:2em;
}

td {
padding:5px;
border-bottom: 1px solid black;
}

td.first, td.second {
width: 15%;
}

td.third {
width: 25%;
}

Using

Spoiler:

<table>
<thead>
<tr>
<th colspan="3">FIRST ROW</th>
</tr>
</thead>

<tbody>
<tr>
<td style="width: 35%">1</td>

<td class="second">2</td>

<td class="third">3</td>
</tr>

<tr>
<td>4</td>

<td>5</td>

<td>6</td>
</tr>

<tr>
<td>7</td>

<td>8</td>

<td>9</td>
</tr>

<tr>
<td>10</td>

<td>11</td>

<td>12</td>
</tr>
</tbody>
</table>

Just some things to consider