code: function removeClass(element, classname) {
  
          // If classList supported, use that
          if (element.classList)
              element.classList.remove(classname);
  
          // Otherwise, manually filter out classes with given name
          else {
              element.className = element.className.replace(/([^ ]+)[ ]*/g,
                  function removeMatchingClasses(match, testClassname) {
  
                      // If same class, remove
                      if (testClassname === classname)
                          return "";
  
                      // Otherwise, allow
                      return match;
                      
                  }
              );
          }
  
      }
docs: Removes a CSS class from an element.
  
  @private
  @function
  @param {Element} element
  The element to remove a class from.
  
  @param {String} classname
  The name of the class to remove.