Modernizr csschecked test

modernizr.csschecked.js

/*!
{
  "name": "CSS checked",
  "property": ":checked",
  "authors": ["richarcher"],
  "tags": ["css"],
  "notes": [{
    "name": "Related Github Issue",
    "href": "https://github.com/Modernizr/Modernizr/issues/845"
  }]
}
!*/
Modernizr.addTest('csschecked', function () {
  return Modernizr.testStyles("#modernizr input {margin-left:0px;} #modernizr input:checked {margin-left: 20px;}", function (elem) {
    var chx = document.createElement('input');
    chx.type = "checkbox";
    chx.checked = "checked";

    elem.appendChild(chx);
    return elem.lastChild.offsetLeft >= 20;
  });
});