JSFiddle - React, Tailwind, and code Playground

HTML

<p>When you rollover me, a simple, humble paragraph, the button below should animate downwards, even if it is selected using a sibling + selector</p>

<a href="#">I should animate!</a>

CSS

a {
    position:relative; display:block; background-color:red; width:50px height:150px;
}

p:hover + a {
  top:50px; -webkit-transition: top 500ms ease-in-out;
  -moz-transition:  top 500ms ease-in-out;
  -o-transition:  top 500ms ease-in-out;
  -ms-transition:  top 500ms ease-in-out;
  transition:  top 500ms ease-in-out
}