JSFiddle - React, Tailwind, and code Playground

HTML

<span id="s1"><span id="s2">Текст</span></span>

CSS

#s1{
display:block;
position:relative;
width: 100px;
height: 100px;
background: red;
}
#s2{
position:absolute;
height:20px;
text-align:center;    
top:0;
bottom:0;
left:0;
right:0;
margin:auto 0;    
}