JSFiddle - React, Tailwind, and code Playground

HTML

<header></header>
<article>
    <p>Conteúdo</p>
    <p>Conteúdo</p>
</article>
<footer></footer>

CSS

html {
    position: relative;
    min-height: 100%;
}
body {
    margin: 0 0 60px;
    /* bottom = footer height */
}
header {
    min-height: 55px;
    background-color: blue;
}
article {
    padding-bottom: 60px;
    width: 900px;
    margin: 0 auto;
}
footer {
    position: absolute;
    bottom: 0px;
    width: 100%;
    height: 60px;
    background-color: green;
}