css/javascript multiple card flip: reset other cards - card-flip

Question

So I'm currently using this one: http://jsfiddle.net/nawdpj5j/10/
Now what I need is that when I flip one card (doesn't matter which one) and then flip another one the first one resets/turnes back.
I think I need to add something in here:
var init = function() {
var flippers = document.getElementsByClassName("flip");
for(i = 0; i < flippers.length; i++){
flippers[i].addEventListener( 'click', function(){
var cardID = this.dataset.targetid;
var card = document.getElementById(cardID);
card.toggleClassName('flipped');
}, false);
}
};
Thank you in advance!

Answer 1

You can get an array of all flipped cards and flip them back whenever a card is flipped like so:
var init = function() {
var flippers = document.getElementsByClassName("flip");
for (i = 0; i < flippers.length; i++) {
flippers[i].addEventListener('click', function() {
var cardID = this.dataset.targetid;
var card = document.getElementById(cardID);
var flipped = document.getElementsByClassName('flipped');
for (i = 0; i < flipped.length; i++) {
if (card !== flipped[i]) {
flipped[i].toggleClassName('flipped');
}
}
card.toggleClassName('flipped');
}, false);
}
};
window.addEventListener('DOMContentLoaded', init, false);
Here is a link to a working demo JS FIDDLE