JSFiddle - React, Tailwind, and code Playground

HTML

<header>
    <h1>h1</h1>
</header>
<div>
    <table>
        <tr>
            <td>td</td>
        </tr>
    </table>
</div>

CSS

body {
  margin: 0;  
  display: flex;
  flex-direction: column;
  height: 100vh;
}
div {
  display: flex;
  flex-direction: column;
  flex: 1;
}
table {
  outline-offset: -1px;
  outline: 1px solid blue;
  display: flex;
  flex-direction: column;
  justify-content: center;
  flex: 1;
}
td {
  outline-offset: -2px;
  outline: 1px solid red;
}