[javascript] Is there a way to add/remove several classes in one single instruction with classList?

Since the add() method from the classList just allows to pass separate arguments and not a single array, you need to invoque add() using apply. For the first argument you will need to pass the classList reference from the same DOM node and as a second argument the array of classes that you want to add:

element.classList.add.apply(
  element.classList,
  ['class-0', 'class-1', 'class-2']
);