JSFiddle - React, Tailwind, and code Playground

HTML

<div>
  <div>
  AAA
  </div>
  <div class="sub-level">
    <div>
    BBB
    </div>
    <div>
      <div class="sub-level">
      CCC
      </div>
    </div>
  </div>
</div>

CSS

.sub-level {
  margin-left: 20px;
}