JSFiddle - React, Tailwind, and code Playground

HTML

<header></header>
<main>This is some content</main>
<footer></footer>

CSS

body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    margin: 0;
}

header, footer {
    background-color: #c9c9c9;
    padding: 20px;
}

main {
    flex: 1;
    margin: 0 auto;
    max-width: 300px;
    border: 1px solid red;
}