JSFiddle - React, Tailwind, and code Playground

HTML

<table class="student_table" border = 1>
    <tr>
        <th class="class_box" colspan="4">Batch 2012</th>
    </tr>
    <tr class="batch_header">
        <td> Hi </td> <!--Have to center this-->
        <td> Hi </td>
        <td> Hi </td>
        <td> Hi </td>
    </tr>
</table>

CSS

.batch_header{
    width: 140px;
    float: left;
}
.batch_header td{
    width:30px;
    height:25px;
    background-color:#EEE;
    margin:0px;
    padding:2.5px;
    border:0px;
    font-weight: bold;
    font-size: smaller;
    text-align:center;    
    vertical-align: middle; <!-- < This is not working-->
}