JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent">
     <div class="child1">
         Hello
     </div>
     <div class="child2">
         world!
     </div> 
 </div>

CSS

.parent {
    display:table;
    height:200px;
    border:1px solid red;
}
.child1, .child2 {
    display:table-cell;
    vertical-align:middle;
}