var div = document.querySelector('div');

var isSpinning = false;

​

document.addEventListener('click', function() {

  if (!isSpinning) start();

  else stop();

});

​

function start() {

  div.classList.add('spin');

  isSpinning = true;

}

​

function stop() {

  div.addEventListener('webkitAnimationIteration', callback);

  div.addEventListener('MSAnimationIteration', callback);

  div.addEventListener('animationiteration', callback);

  function callback() {

    div.removeEventListener('webkitAnimationIteration', callback);

    div.removeEventListener('MSAnimationIteration', callback);

    div.removeEventListener('animationiteration', callback);

    div.classList.remove('spin');

    isSpinning = false;

  }

}