JSFiddle - React, Tailwind, and code Playground

by FWeinb

HTML

<script src="http://modernizr.com/downloads/modernizr-2.5.3.js"></script>
<div class="vw"></div>

CSS

.vw { width: 50vw; height: 10px; background: green; }

JavaScript

Modernizr.addTest("viewportunits", function() { 
    var bool;
    
    Modernizr.testStyles("#modernizr { width: 50vw; }", function(elem, rule) {   
        var width = parseInt(window.innerWidth/2,10),
            compStyle = parseInt((window.getComputedStyle ?
                      getComputedStyle(elem, null) :
                      elem.currentStyle)["width"],10);
        
        bool= !!(compStyle == width);
    });
    
    return bool;
});

alert(Modernizr.viewportunits);