JSFiddle - React, Tailwind, and code Playground

HTML

main<span class="sub">x</span><span class="super">y</span>

CSS

.sub, .super {
  font-size: 75%;
  line-height: 0;
  //position: relative;
  //vertical-align: baseline;
}
 
.super {
  vertical-align: super;
}
 
.sub {
  vertical-align: sub;
}