<style>

.tb

{

     width: 1600px;

     text-align: center;

     border-collapse: collapse;

}

.tb tr td

{

    border:1px solid #dcdddd;

}

</style>

<table class="tb" cellpadding="0" cellspacing="0">

    <tr>

        <td>aaa</td>

        <td>bbc</td>

        <td>ccc</td>

    </tr>

    <tr>

        <td>aaa</td>

        <td>ddd</td>

        <td>eee</td>

    </tr>

    <tr>

        <td>ddd</td>

        <td>ddd</td>

        <td>ddd</td>

    </tr>

</table>