.slide-board {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.45rem;
  max-width: 340px;
  padding: 0.65rem;
  background: #CBD5E1;
  border-radius: 16px;
}

.slide-tile {
  aspect-ratio: 1;
  border: none;
  border-radius: 10px;
  background: linear-gradient(135deg, #7C3AED, #6D28D9);
  color: #fff;
  font-family: var(--font-display, 'Fredoka', sans-serif);
  font-size: clamp(1.1rem, 5vw, 1.4rem);
  font-weight: 700;
  cursor: pointer;
  min-height: 44px;
  transition: transform 0.15s, box-shadow 0.15s;
  box-shadow: 0 3px 10px rgba(124, 58, 237, 0.3);
}

.slide-tile:hover:not(:disabled) {
  transform: scale(1.04);
}

.slide-tile:disabled,
.slide-tile.empty {
  background: rgba(255, 255, 255, 0.35);
  box-shadow: none;
  cursor: default;
}

.slide-tile.correct {
  background: linear-gradient(135deg, #10B981, #059669);
}