JSFiddle - React, Tailwind, and code Playground

HTML

<div class="clickme">JavaScript</div>
<a class="clickme" id="anchor" href="#anchor">:target</a>

CSS

.clickme {
    /* irrelevant */
    display: none;
    border-radius: 7px;
    width: 100px;
    height: 10px;
    line-height: 100px;
    text-align: center;
    margin: 50px auto;
    color: white;
    cursor: pointer;
    
    background: #222;
    
    -o-transition: background 2s;
    -moz-transition: background 2s;
    -webkit-transition: background 2s;
    transition: display 1s;
}

.active, .clickme:target {
    display:block;
}

JavaScript

var element = document.querySelector("div.clickme");
element.addEventListener("click", function() {
    this.classList.toggle("active");
});