JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <img src="http://lorempixel.com/400/200/">
  <div class="cover"></div>
  </div>
</div>

<div class="container">
  <img src="http://lorempixel.com/400/800/">
  <div class="cover"></div>
</div>

CSS

.container {
  position: relative;
  display: block;
  height: 300px;
  width: 300px;
  background-color: #000;
  border: 2px solid red;
}
.container img {
  max-width: 100%;
  max-height: 100%;
  position: absolute;
  display: block;
  top: 50%;
  left: 50%;
  transform: translate(-50%,-50%);
}
.cover {
  display: none;
}
.container:hover .cover{
  display: block;
  position: absolute;
  top: 0px;
  left: 0px;
  height: 100%;
  width: 100%;
  background-color: #FFF;
  opacity: 0.8;
}