JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent">
    <span style="font-size=30px"> <span style="font-size=200%"> TEST </span>  </span>  
    <span style="font-size=11px> TEST </span>  
</div>

CSS

/*
.parent span {
font-size:200%;
}
*/