JSFiddle - React, Tailwind, and code Playground

HTML

<div id="box-cntnr">
  <div class="box" id="b1">box 1</div>
  <div class="box" id="b2">box 2</div>
</div>

CSS

.box {
  width: 100px;
  height: 100px;
  background-color: lightblue;
  margin: 10px;
}

#box-cntnr {
  display: flex;
}

#b1 {
  align-self: center;
}