/* Import Google Font - Poppins */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600;700&display=swap');
*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
}
body{
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  padding: 24px 12px;
  min-height: 100vh;
  background: #6563FF;
}
.wrapper{
  padding: 25px;
  border-radius: 10px;
  background: #F8F8F8;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
  width: 100%;
  max-width: 450px;
}
.cards{
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  list-style: none;
}
.card, .view{
  display: flex;
  align-items: center;
  justify-content: center;
}
.cards .card{
  cursor: pointer;
  list-style: none;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
  position: relative;
  perspective: 1000px;
  transform-style: preserve-3d;
  aspect-ratio: 1 / 1;
  min-height: 64px;
}
.card.shake{
  animation: shake 0.35s ease-in-out;
}
@keyframes shake {
  0%, 100%{
    transform: translateX(0);
  }
  20%{
    transform: translateX(-13px);
  }
  40%{
    transform: translateX(13px);
  }
  60%{
    transform: translateX(-8px);
  }
  80%{
    transform: translateX(8px);
  }
}
.card .view{
  width: 100%;
  height: 100%;
  position: absolute;
  inset: 0;
  border-radius: 7px;
  background: #fff;
  pointer-events: none;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  box-shadow: 0 3px 10px rgba(0,0,0,0.1);
  transition: transform 0.25s linear;
}
.card .front-view img{
  width: 19px;
}
.card .back-view img{
  max-width: 45px;
}
.card .back-view{
  transform: rotateY(-180deg);
}
.card.flip .back-view{
  transform: rotateY(0);
}
.card.flip .front-view{
  transform: rotateY(180deg);
}

@media screen and (max-width: 700px) {
  .wrapper{ padding: 18px; }
  .cards{ gap: 8px; }
  .card .front-view img{
    width: 17px;
  }
  .card .back-view img{
    max-width: 40px;
  }
}

@media screen and (max-width: 530px) {
  .wrapper{ padding: 14px; }
  .cards{ gap: 6px; }
  .card .front-view img{
    width: 15px;
  }
  .card .back-view img{
    max-width: 35px;
  }
}
.brand{text-align:center;color:#fff}
.brand h1{font-size:26px;letter-spacing:3px;text-shadow:0 2px 12px rgba(0,0,0,.25)}
.brand p{font-size:14px;opacity:.9;margin-top:6px}
.brand b{color:#ffe27a}
.credit{color:#fff;font-size:12px;opacity:.85;text-align:center}