.red { background-color : red }
.t1 td:not(:last-child) { background-color : lime }
p > *:not(:last-child) { background-color : lime }
table.t1 td { border : thin black solid }

 <div>
  <table class="t1" border="1">
   <tr>
    <td class="red">green cell</td>
    <td class="red">green cell</td>
    <td>1.3</td>
   </tr>
   <tr>
    <td class="red">green cell</td>
    <td class="red">green cell</td>
    <td>2.3</td>
   </tr>
   <tr>
    <td class="red">green cell</td>
    <td class="red">green cell</td>
    <td>3.3</td>
   </tr>
  </table>
 </div>
 <p>This <span>paragraph should</span> be unstyled.</p>