JSFiddle - React, Tailwind, and code Playground

HTML

<div class="needle">a</div>
<div>a</div>
<div>a</div>
<div>a</div>
<div>a</div>
<div>a</div>
<div>a</div>
<div>a</div>
<div>a</div>
<div>a</div>

JavaScript

var className = "needle";
var divs = document.getElementsByTagName('div'),
    len = divs.length,
    i = 0;

for (i; i < len; i++) {
    divs[i].onclick = climb;
}

function climb(event) {
    var element = event.target;
    while(element.previousSibling.className != className) {
       element = element.previousSibling;
    }
    
    alert(element.previousSibling.className)
    
}