JSFiddle - React, Tailwind, and code Playground

HTML

<div class="fadeInAndOut">
Hello
</div>

CSS

.fadeInAndOut {
  animation: fadeinout 14s linear forwards;
}

@keyframes fadeinout {

  0%,
  100% {
    opacity: 0;
  }
  
  14%, 86% {
    opacity: 1;
  }
}