Revert flipping a DIV after clicking on another

Check out the link. If you click on a product, it will flip over and display some information. You can flip all products at a specific point in time.

I only want one product upside down. Every time someone clicks on a different product, I want the previous one to return to its original appearance.

html:

<div class="card effect__EFFECT">
  <div class="card__front">
    <span class="card__text">front</span>
  </div>
  <div class="card__back">
    <span class="card__text">back</span>
  </div>
</div>

      

        
        
        
      

    

Javascript:

(function() {
  var cards = document.querySelectorAll(".card.effect__click");
  for ( var i  = 0, len = cards.length; i < len; i++ ) {
    var card = cards[i];
    clickListener( card );
  }

  function clickListener(card) {
    card.addEventListener( "click", function() {
      var c = this.classList;
      c.contains("flipped") === true ? c.remove("flipped") : c.add("flipped");
    });
  }
})();

      

        
        
        
      

    

CSS:

.card.effect__click.flipped .card__front {
  -webkit-transform: rotateY(-180deg);
          transform: rotateY(-180deg);
}

.card.effect__click.flipped .card__back {
  -webkit-transform: rotateY(0);
          transform: rotateY(0);
}