JSFiddle - React, Tailwind, and code Playground
HTML
<div id="test">i am the text</div>
JavaScript
var test = document.getElementById('test');
alert( getStyle('test', 'line-height' ) );
function getStyle(el,styleProp)
{
var x = document.getElementById(el);
if (x.currentStyle)
var y = x.currentStyle[styleProp];
else if (window.getComputedStyle)
var y = document.defaultView.getComputedStyle(x,null).getPropertyValue(styleProp);
return y;
}