@import url('https://fonts.googleapis.com/css?family=Roboto&display=swap');
html{
    min-height:100%;
    position:relative;
}
body{
        margin: 0px;
    background-color: #BCCCDC;
    font-family: 'Roboto', sans-serif;
}
.game{
    position:absolute;
    top:0;
    bottom:0;
    left:0;
    right:0;
    overflow:hidden;
    
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    grid-template-rows: 1fr 1fr 1fr;
    grid-template-areas: 
    'card1 card2 card3 card4' 
    'card5 card6 card7 card8'
    'card9 card10 card11 card12';
    grid-gap: 20px;
    padding: 20px;
}






.card{
    position: relative;
    height: 100%;
    background-color: #fff;
    width: 100%;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
	transition: 0.6s;
	transform-style: preserve-3d;
}
.card.active{
    /*border: 4px solid #334E68; */
}



.card>.front{
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
background-color: #fff;
    display: grid;
    place-items: center;
    font-size: 40px;
    color: #0F609B;
    z-index: 2;
    transform: rotateY(0deg);
}
.card>.back{
    display: none;
    transform: rotateY(180deg);
}

.card.active{
   transform: rotateY(180deg); 
}

.card.active>.front{
    display: none;
}
.card.active>.back{
    display: block;
    background-position: center;
    background-repeat: no-repeat;
    height: 100%;
    width: 100%;
    background-size: cover;
    transform: rotateY(180deg);
}

.card.won{
    transform: scale(0.9) rotateY(180deg);
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
}