JSFiddle - React, Tailwind, and code Playground

HTML

<div id="test">
		<div id="sumup">
			
			<h1 class="titre">Title</h1>
			<div id="date">hello guys</div>
		</div>
	</div>

CSS

#test {
    display:table; 
    width:100%;
    height : 400px;
}

#sumup {
    display:table-cell;
    vertical-align:middle;
	width : 100%;
    height : 100%;
   	background-color: #123456;
}