JSFiddle - React, Tailwind, and code Playground

HTML

<div class="icons">
    <span class="hoverme">Hover Me</span>
    <div id="hover1">First</div>
</div>

CSS

.icons > div[id] {
    opacity: 0;
    height: 100px;
    width: 100px;
    background: red;
    -moz-transition: opacity .5s;
    -webkit-transition: opacity .5s;
    transition: opacity .5s;
}

.icons > span {
    display: block;
}

.icons > span:hover + div {
    opacity: 1;
}