JSFiddle - React, Tailwind, and code Playground

HTML

<div class="my_class" id="1">
  <div class="overlay"></div>
</div>

<div class="my_class" id="2">
  <div class="overlay"></div>
</div>

<div class="my_class" id="3">
  <div class="overlay"></div>
</div>

<div class="my_class" id="4">
  <div class="overlay"></div>
</div>

CSS

.my_class {
  background-color: red;
  height: 50px;
  margin: 5px 0;
}

.overlay {
  background-color: yellow;
  width: 10000px;
  height: 50px;
}

JavaScript

$('.my_class').mouseenter(function() {
  $(this).children('.overlay').fadeTo(1000, 1);
})

$('.my_class').mouseleave(function() {
  $(this).children('.overlay').fadeTo(1000, 0);
})