/* Memory Match Styles */

.difficulty-bar {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}

.diff-btn {
  padding: 0.4rem 1.1rem;
  border: 1px solid var(--bg-glass-border);
  background: var(--bg-glass);
  color: var(--text-secondary);
  border-radius: var(--radius-full);
  font-family: var(--font-primary);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-base);
}

.diff-btn.active {
  background: rgba(236, 72, 153, 0.15);
  border-color: rgba(236, 72, 153, 0.3);
  color: #ec4899;
}

.diff-btn:hover:not(.active) {
  background: var(--bg-card-hover);
}

.board-container { position: relative; }

.mem-board {
  display: inline-grid;
  gap: 10px;
  padding: 14px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-xl);
}

.mem-card {
  width: 72px;
  height: 72px;
  perspective: 600px;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

.mem-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.45s cubic-bezier(0.4, 0, 0.2, 1);
  transform-style: preserve-3d;
}

.mem-card.flipped .mem-card-inner,
.mem-card.matched .mem-card-inner {
  transform: rotateY(180deg);
}

.mem-card-face {
  position: absolute;
  inset: 0;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  font-size: 1.8rem;
}

.mem-card-back {
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.06);
  transition: background 0.15s;
}

.mem-card:hover:not(.flipped):not(.matched) .mem-card-back {
  background: rgba(255, 255, 255, 0.11);
}

.mem-card-front {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.06);
  transform: rotateY(180deg);
}

.mem-card.matched .mem-card-front {
  background: rgba(16, 185, 129, 0.1);
  border-color: rgba(16, 185, 129, 0.2);
  box-shadow: 0 0 20px rgba(16, 185, 129, 0.1);
}

.mem-card.matched {
  animation: matchPop 0.4s ease;
}

@keyframes matchPop {
  0% { transform: scale(1); }
  50% { transform: scale(1.12); }
  100% { transform: scale(1); }
}

/* Overlay */
.mem-overlay {
  position: absolute;
  inset: 0;
  background: rgba(10, 10, 15, 0.88);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-radius: var(--radius-xl);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  transition: var(--transition-base);
}

.mem-overlay.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.mem-overlay-content { text-align: center; }
.mem-overlay-icon { font-size: 3rem; margin-bottom: 0.75rem; }

.mem-overlay-content h2 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 0.4rem;
}

.mem-overlay-content p {
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
}

/* Size 6x6 */
.mem-board.size-6 .mem-card {
  width: 58px;
  height: 58px;
}

.mem-board.size-6 .mem-card-face {
  font-size: 1.4rem;
}

@media (max-width: 480px) {
  .mem-card { width: 60px; height: 60px; }
  .mem-card-face { font-size: 1.5rem; }
  .mem-board { gap: 6px; padding: 8px; }
  .mem-board.size-6 .mem-card { width: 46px; height: 46px; }
  .mem-board.size-6 .mem-card-face { font-size: 1.1rem; }
}