tr:nth-child(odd) {
background-color: lightskyblue;
}
tr:nth-child(even) {
background-color: lightpink;
}
th {
background-color: lightseagreen;
}<table class="table table-sm">
...
</table><table class="table table-dark">
<thead>
<tr>
<th scope="col">#</th>
<th scope="col">First</th>
<th scope="col">Last</th>
<th scope="col">Handle</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">1</th>
<td>Mark</td>
<td>Otto</td>
<td>@mdo</td>
</tr>
<tr>
<th scope="row">2</th>
<td>Jacob</td>
<td>Thornton</td>
<td>@fat</td>
</tr>
<tr>
<th scope="row">3</th>
<td>Larry</td>
<td>the Bird</td>
<td>@twitter</td>
</tr>
</tbody>
</table>// Add the table and table striped class from bootstrap
<table class="table table-striped">