JSFiddle - React, Tailwind, and code Playground

HTML

<div class="js-block block _active">
    <div class="link">link 1</div>
    <div class="content">123</div>
</div>
<div class="js-block block">
    <div class="link">link 2</div>
</div>
<div class="js-block block">
    <div class="link">link 3</div>
    <div class="content">5</div>
</div>
<div class="js-block block">
    <div class="link">link 3</div>
    <div class="content">456</div>
</div>
<div class="test">
 ss
</div>
    <div class="content">234</div>

CSS

.block {width:100px; float: left; margin: 10px;}
.block .link {color: blue; text-decoration: underline;}
.block .content {
    display: none;
    padding: 20px;
    background: red;
}
.block._active .content {
    display: block;
}
.test{
  display: block;
  position: relative;
  height: 100px;
}

JavaScript

var blocks = document.getElementsByClassName('js-block');

[].forEach.call(blocks, function (block) {
    block.onclick = function() {
        [].forEach.call(blocks, function (block) {
            block.className= "js-block block";
        });
        block.className= "js-block block _active";
    }
});