* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

body {
  height: 100vh;
  display: flex;
}

.commentaire{
	text-align: center;
	font-size: 40px;
	font-weight: bold;
}



.front-face,
.back-face {
  width: 100%;
  height: 100%;
  padding: 20px;
  position: absolute;
  border-radius: 5px;
  backface-visibility: hidden;
}

.memory-card {
  width: calc(25% - 10px);
  height: calc(33.333% - 10px);
  margin: 5px;
  position: relative;
  border: 3px solid black;
  border-radius: 5px;
  transform: scale(1);
  transform-style: preserve-3d;
 transition: transform .5s;
}

 .memory-card:active {
   transform: scale(0.97);
   transition: transform .2s;
 }
 
 .memory-card.flip {
  transform: rotateY(180deg);
}

.memory-game {
  width: 500px;
  height: 500px;
  margin: auto;
  display: flex;
  flex-wrap: wrap;
}

@media screen and (max-width:600px){
	.memory-game {
	  width: 1fr;
	  height: 1fr;
	}
}


.front-face {
  transform: rotateY(180deg);
}