.bk{ border-collapse:collapse; }
.bk td{ border:1px solid #CCC;}
<style>
  
.style1 td{ border:1px solid #CCC;}
        .style1
        {
            width: 100%;
            border-collapse:collapse;
        }
    </style>
    <table class="style1">
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
       
    </table>