JSFiddle - React, Tailwind, and code Playground
by oti ext
HTML
<div id="wrap"></div>
<div>
<div></div>
<div></div>
<div></div>
<div></div>
<div class="item"></div>
</div>
<div></div>
<div></div>
JavaScript
var item = document.querySelectorAll('.item')[0];
var wrap = document.querySelectorAll('#wrap')[0];
function countNth(node) {
var i = 1;
while (node = node.previousElementSibling)
++i;
return i;
}
alert(countNth(item)); // => 5
alert(countNth(wrap)); // => 1