JSFiddle - React, Tailwind, and code Playground

HTML

<table class="mytable">
<thead>
  <tr><th>Spalte 1</th><th>Spalte 2</th></tr>
</thead>
<tbody>
  <tr><td>Zeile 1-1</td><td>Zeile 1-2</td></tr>
  <tr><td>Zeile 2-1</td><td>Zeile 2-2</td></tr>
  <tr><td>Zeile 3-1</td><td>Zeile 3-2</td></tr>
</tbody>
</table>

CSS

.mytable {
  border: 1px solid silver;
  border-collapse: collapse;
}

.mytable td {
  border: 1px solid silver;
  background-color: white;
}

.mytable tbody tr:first-child td {
  background-color: #005F6B;
}