modernizr/feature-detects/css/hsla.js

Modernizr is a JavaScript library that detects HTML5 and CSS3 features in the user’s browser.

/*!
{
  "name": "CSS HSLA Colors",
  "caniuse": "css3-colors",
  "property": "hsla",
  "tags": ["css"],
  "notes": ["Same as rgba(), in fact, browsers re-map hsla() to rgba() internally, except IE9 who retains it as hsla"]
}
!*/
define(['Modernizr', 'createElement', 'contains'], function( Modernizr, createElement, contains ) {
  Modernizr.addTest('hsla', function() {
    var elem = createElement('div');
    var style = elem.style;
    style.cssText = 'background-color:hsla(120,40%,100%,.5)';
    return contains(style.backgroundColor, 'rgba') || contains(style.backgroundColor, 'hsla');
  });
});