.memory-layout {
  display: grid;
  grid-template-columns: minmax(230px, 310px) minmax(0, 1fr);
  gap: 18px;
  max-width: 1220px;
  margin: 0 auto;
}

.memory-panel {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 18px;
  background: linear-gradient(160deg, rgba(188, 232, 214, 0.94), rgba(255, 253, 245, 0.9));
}

.hint {
  margin-bottom: 0;
  color: #405363;
  font-size: 1.08rem;
  font-weight: 850;
  line-height: 1.55;
}

.card-board {
  display: grid;
  grid-template-columns: repeat(var(--columns, 4), minmax(72px, 1fr));
  gap: 12px;
}

.memory-card {
  position: relative;
  aspect-ratio: 1;
  min-height: 72px;
  border-radius: 24px;
  cursor: pointer;
  background: transparent;
  perspective: 700px;
}

.memory-card:disabled {
  cursor: default;
}

.card-inner {
  position: absolute;
  inset: 0;
  border-radius: inherit;
  transform-style: preserve-3d;
  transition: transform 260ms ease;
}

.memory-card.is-open .card-inner,
.memory-card.is-matched .card-inner {
  transform: rotateY(180deg);
}

.card-face {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  border: 3px solid rgba(255, 255, 255, 0.76);
  border-radius: inherit;
  backface-visibility: hidden;
  box-shadow: 0 12px 20px rgba(71, 85, 105, 0.14);
  font-size: clamp(2rem, 6vw, 4rem);
  font-weight: 950;
}

.card-front {
  background: linear-gradient(145deg, #ffe089, #ffd1b8);
  color: #405363;
}

.card-back {
  background: var(--card-bg, #b9e5ff);
  transform: rotateY(180deg);
}

.memory-card.is-matched {
  opacity: 0.45;
}

@media (max-width: 820px) {
  .memory-layout {
    grid-template-columns: 1fr;
  }

  .memory-panel {
    gap: 12px;
  }
}

@media (max-width: 520px) {
  .card-board {
    gap: 9px;
  }

  .memory-card {
    border-radius: 18px;
    min-height: 62px;
  }
}