Remove multiple classes with prefix

HTML

<p>Remember to inspect element on the input below</p>
<div class="custom-nf">
  <div class="input nf-input-outer nf-validation">
    <div class="nf-container">
      <div class="nf-outer nf-outer-input nf-outer-validation">
        <div class="nf-middle">
          <div class="nf-inner">
            <label for="dummy" class="nf-label"></label>
            <input id="dummy" type="text" class="nf-input">
          </div>
        </div>
      </div>
    </div>
  </div>
</div>

JavaScript

var nfClasses = document.querySelectorAll('.custom-nf [class*="nf-"]');
Array.prototype.forEach.call(nfClasses, function(element) {
  var classListCopy = Array.prototype.slice.call(element.classList);
  classListCopy.forEach(function(className) {
    if (className.match(/^nf\-/)) {
      element.classList.remove(className);
    }
  });
});