JSFiddle - React, Tailwind, and code Playground

HTML

<div class="flex-container">
  <button>Button in flex</button>
</div>
<div class="normal-container">
  <button>Button in normal</button>
</div>

CSS

.flex-container{
  display:flex;
  background:yellow;
}

.normal-container{
  background:green;

}

button{
  margin : 0px auto;
  display: block;
}