.coin {
  height: 200px;
  width: 200px;
  position: relative;
  margin: 25px auto 50px;
  -webkit-transform-style: preserve-3d;
  transform-style: preserve-3d;
}
.coin img {
  width: 100%;
}
.heads, .tails {
  position: absolute;
  width: 100%;
  height: 100%;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
}
.tails {
  transform: rotateX(180deg);
}
button {
  background: #ebd557;
  width: 150px;
  padding: 15px 0;
  border: none;
  font-size: 1rem;
  border-radius: 5px;
  color: #3e3e3e;
  font-weight: 700;
  cursor: pointer;
  transition: 0.2s;
}
button:hover {
  background: #f8e26a;
}
button:disabled {
  background: #aaaaaa;
}
@keyframes spin-tails {
  0% {
    transform: rotateX(0);
  }
  100% {
    transform: rotateX(900deg);
  }
}
@keyframes spin-heads {
  0% {
    transform: rotateX(0);
  }
  100% {
    transform: rotateX(1080deg);
  }
}