JSFiddle - React, Tailwind, and code Playground

by Tiago Sousa

HTML

<input type="checkbox" id="my_chk">
<label class="btn" for="my_chk"><img src="http://placekitten.com.s3.amazonaws.com/homepage-samples/200/140.jpg" id="btnLeft" /></label>

CSS

#my_chk {
  display: none;
}
#my_chk + label > img {
  -webkit-transition: opacity 2s; /* Safari */
  transition: opacity 2s;  
}
#my_chk:checked + label > img {
  opacity: 0.5;
}