body {
  font-family: Inter, sans-serif;
}
.tool-card {
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 0.75rem;
  padding: 1.25rem;
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.04);
}
.score-pill {
  background: #1f2937;
  border-radius: 8px;
  padding: 5px 10px;
  text-align: center;
  min-width: 52px;
}
.score-pill .label {
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: #9ca3af;
  text-transform: uppercase;
}
.score-pill .value {
  font-size: 17px;
  font-weight: 800;
  color: #fff;
  line-height: 1.25;
}
.diff-btn {
  border: 1px solid #e5e7eb;
  border-radius: 99px;
  padding: 4px 12px;
  font-size: 12px;
  font-weight: 600;
  color: #6b7280;
  background: #fff;
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}
.diff-btn:hover {
  border-color: #6ee7b7;
  color: #065f46;
  background: #f0fdf4;
}
.diff-btn.active {
  border-color: #059669;
  color: #065f46;
  background: #ecfdf5;
}

/* Puzzle grid */
#puzzle-grid {
  display: grid;
  gap: 6px;
  max-width: 340px;
  margin: 0 auto;
  touch-action: none;
  user-select: none;
}

.tile {
  aspect-ratio: 1;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  cursor: pointer;
  transition:
    transform 0.12s ease,
    box-shadow 0.12s ease;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: #fff;
  box-shadow:
    0 3px 8px rgba(5, 150, 105, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
  position: relative;
}
.tile:hover {
  transform: scale(1.04);
  box-shadow: 0 5px 14px rgba(5, 150, 105, 0.35);
}
.tile:active {
  transform: scale(0.95);
}
.tile.empty {
  background: #f3f4f6;
  box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.08);
  cursor: default;
  pointer-events: none;
}
.tile.movable {
  cursor: pointer;
}
.tile.movable::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 10px;
  border: 2px solid rgba(255, 255, 255, 0.4);
}

/* Solved state */
.tile.solved-flash {
  animation: solvedPop 0.35s ease forwards;
}
@keyframes solvedPop {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.08);
    background: linear-gradient(135deg, #10b981, #059669);
  }
  100% {
    transform: scale(1);
  }
}

#win-banner {
  display: none;
  text-align: center;
  background: #ecfdf5;
  border: 1px solid #6ee7b7;
  border-radius: 10px;
  padding: 12px;
  font-size: 15px;
  font-weight: 700;
  color: #065f46;
  margin-bottom: 12px;
}
#win-banner.show {
  display: block;
}

#toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(0);
  background: #1f2937;
  color: #fff;
  padding: 10px 20px;
  border-radius: 99px;
  font-size: 13px;
  font-weight: 600;
  pointer-events: none;
  opacity: 0;
  transition:
    opacity 0.3s,
    transform 0.3s;
  z-index: 999;
  white-space: nowrap;
}
#toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(-8px);
}

.related-game-card {
  display: flex;
  align-items: center;
  gap: 10px;
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 10px;
  padding: 10px 12px;
  text-decoration: none;
  color: inherit;
  transition:
    border-color 0.15s,
    box-shadow 0.15s,
    transform 0.15s;
}
.related-game-card:hover {
  border-color: #6ee7b7;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.07);
  transform: translateY(-1px);
}
.related-icon {
  width: 40px;
  height: 40px;
  border-radius: 9px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}