.memory-game{display:grid;gap:20px;grid-template-columns:repeat(2,1fr)}@media(min-width:768px){.memory-game{grid-template-columns:repeat(3,1fr)}}@media(min-width:1024px){.memory-game{grid-template-columns:repeat(4,1fr)}}.card{cursor:pointer;perspective:1000px}.card.flipped .card-front{transform:rotateY(0)}.card.flipped .card-back{transform:rotateY(180deg)}.card-back,.card-front{backface-visibility:hidden;border-radius:10px;height:100%;left:0;position:absolute;top:0;transition:transform .3s;width:100%}.card-front{transform:rotateY(180deg)}.card-back{transform:rotateY(0)}