JSFiddle - React, Tailwind, and code Playground

HTML

<body>

<table>
	<tbody>
		<tr class="alt">
			<td class="cell main">Row 1 Cell 1
        <div class="xxx">
        teste
        </div>
      </td>
			<td class="cell">Row 1 Cell 2</td>
			<td class="cell main">Row 1 Cell 3</td>
		</tr>
		<tr>
			<td class="cell">Row 2 Cell 1</td>
			<td class="cell">Row 2 Cell 2</td>
			<td class="cell">Row 2 Cell 3</td>
		</tr>
		<tr>
			<td class="cell">Row 3 Cell 1</td>
			<td class="cell">Row 3 Cell 2</td>
			<td class="cell">Row 3 Cell 3</td>
		</tr>
	</tbody>
</table>
</body>

CSS

tbody :not(.alt) .xxx {
    background-color:red;
}

body :not(.modal) .teste {
  background-color:blue;
}