JSFiddle - React, Tailwind, and code Playground

HTML

<table>
    <th>a</th>
    <th class="b">b</th>
    <th>a</th>
    <tbody>
        <tr>
        <td>1</td>
        <td>2</td>
        <td>3</td>
        </tr>
        <tr>
        <td>1</td>
        <td>2</td>
        <td>3</td>
        </tr>
        <tr>
        <td>1</td>
        <td>2</td>
        <td>3</td>
        </tr>
        <tr>
        <td>1</td>
        <td>2</td>
        <td>3</td>
        </tr>
    </tbody>

CSS

.b { color: red; }
table td:nth-child(2) { color: red }