JSFiddle - React, Tailwind, and code Playground

HTML

<div class="my-flex-container">
    	<div class="my-flex-block">item1</div>
	    <div class="my-flex-block">item2</div>
	    <div class="my-flex-block">item3</div>
    </div>

CSS

.my-flex-container{
	/*height: 200px;
	border: 1px solid;*/
    background: #569;
}
body {
    height: 100%;
    display: flex;
	flex-direction: column;
	justify-content: center;
    background: #578;
}
html, body {
    height: 100%;
}