JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
    <div class="wrapper_in">
        <header>Header</header>
        <div class="content">Content</div>
    </div>
    <footer>Footer</footer>
</div>

CSS

html, body {
    margin: 0;
    padding: 0;
    height: 100%;
}

.wrapper {
    min-height: 100%;
    position: relative;
}

.wrapper_in {
    padding-bottom: 30px;
}

header {
    background-color: #f00;
    color: #fff;
    height: 30px;
}

.content {
    background-color: #0f0;
    color: #fff;
}

footer {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: #00f;
    color: #fff;
}