/* Standard Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--border-radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-normal);
  outline: none;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  text-align: center;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), #4c1d95);
  color: white;
  border: 1px solid rgba(255, 255, 255, 0.1);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px var(--color-primary-glow);
}
.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-main);
  border: 1px solid var(--border-color);
}
.btn-secondary:hover {
  background: var(--bg-card-hover);
  color: var(--text-bright);
  border-color: var(--text-muted);
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--color-primary);
  color: var(--text-bright);
}
.btn-outline:hover {
  background: var(--color-primary-glow);
  box-shadow: 0 0 15px var(--color-primary-glow);
}

/* Glassmorphic & Neon Cards */
.card {
  background: var(--bg-card);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 30px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  transition: border-color var(--transition-normal), box-shadow var(--transition-normal);
}

.card:hover {
  border-color: var(--border-glow);
  box-shadow: 0 10px 40px var(--border-glow);
}

/* The Tic-Tac-Toe Board Grid */
.board-container {
  position: relative;
  width: 100%;
  max-width: 380px;
  margin: 0 auto;
}

.board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(3, 1fr);
  gap: 12px;
  background: var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 12px;
  aspect-ratio: 1 / 1;
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5);
  position: relative;
}

.cell {
  background: var(--bg-main);
  border-radius: var(--border-radius-md);
  border: 1px solid var(--border-color);
  aspect-ratio: 1 / 1;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  outline: none;
  font-size: 3rem;
  font-family: var(--font-title);
  font-weight: 800;
  user-select: none;
  transition: all var(--transition-fast);
  position: relative;
}

.cell:focus-visible {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-glow);
}

/* X and O visual styles */
.cell.x {
  color: var(--color-x);
  text-shadow: 0 0 10px var(--color-x-glow), 0 0 20px var(--color-x-glow);
  animation: markScale 0.25s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.cell.o {
  color: var(--color-o);
  text-shadow: 0 0 10px var(--color-o-glow), 0 0 20px var(--color-o-glow);
  animation: markScale 0.25s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

/* Preview mark on hover (Accessibility and desktop hint) */
@media (hover: hover) {
  .cell:not(.x):not(.o):hover::after {
    opacity: 0.25;
    font-size: 2.8rem;
  }
  body[data-current-turn="X"] .cell:not(.x):not(.o):hover::after {
    content: "X";
    color: var(--color-x);
    text-shadow: 0 0 5px var(--color-x-glow);
  }
  body[data-current-turn="O"] .cell:not(.x):not(.o):hover::after {
    content: "O";
    color: var(--color-o);
    text-shadow: 0 0 5px var(--color-o-glow);
  }
}

@keyframes markScale {
  0% {
    transform: scale(0.4);
    opacity: 0;
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

/* Win Lines / Winning Cells Highlight */
.cell.winner {
  background: var(--border-color);
  animation: pulseWinner 1.5s infinite alternate;
}

@keyframes pulseWinner {
  0% {
    transform: scale(1);
    box-shadow: inset 0 0 5px rgba(255, 255, 255, 0.1);
  }
  100% {
    transform: scale(0.96);
    box-shadow: inset 0 0 25px var(--color-primary-glow), 0 0 10px var(--color-primary-glow);
  }
}

/* Glass Modals (Alerts/Rematch Dialogs) */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(5px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-content {
  background: var(--bg-card);
  border: 1px solid var(--border-glow);
  box-shadow: 0 10px 40px var(--color-primary-glow);
  border-radius: var(--border-radius-lg);
  padding: 35px;
  width: 90%;
  max-width: 450px;
  text-align: center;
  transform: translateY(20px);
  transition: transform var(--transition-normal);
}

.modal-overlay.open .modal-content {
  transform: translateY(0);
}

.modal-title {
  font-size: 1.8rem;
  margin-bottom: 15px;
}

.modal-desc {
  margin-bottom: 25px;
  color: var(--text-muted);
}

.modal-actions {
  display: flex;
  gap: 15px;
  justify-content: center;
}

/* Achievements drawer */
.achievements-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 15px;
  margin-top: 20px;
}

.achievement-card {
  background: rgba(0, 0, 0, 0.2);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  padding: 15px 10px;
  text-align: center;
  opacity: 0.4;
  filter: grayscale(100%);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.achievement-card.unlocked {
  opacity: 1;
  filter: grayscale(0%);
  border-color: var(--color-success);
  background: rgba(16, 185, 129, 0.05);
  box-shadow: 0 4px 10px rgba(16, 185, 129, 0.1);
}

.achievement-icon {
  font-size: 2rem;
}

.achievement-title {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-bright);
}

.achievement-desc {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Google AdSense placeholders */
.ad-slot {
  margin: 20px auto;
  padding: 10px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px dashed var(--border-color);
  border-radius: var(--border-radius-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  max-width: 100%;
  overflow: hidden;
  position: relative;
  transition: all var(--transition-normal);
}

.ad-slot::before {
  content: "SPONSORED ADVERTISEMENT";
  font-size: 0.65rem;
  letter-spacing: 1px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.ad-slot-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  border: 1px solid var(--border-color);
  padding: 6px 12px;
  border-radius: 4px;
}

/* Simulated AdSense banner types */
.ad-leaderboard {
  width: 728px;
  height: 90px;
  max-width: 100%;
}

.ad-rectangle {
  width: 300px;
  height: 250px;
}

.ad-sticky-bottom {
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: 728px;
  height: 50px;
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
  z-index: 90;
  margin: 0;
  padding: 5px;
  box-shadow: 0 -5px 15px rgba(0, 0, 0, 0.3);
}

/* Premium Mode hides ads */
body.premium-active .ad-slot {
  display: none !important;
}

/* Stats Counter Badge */
.stat-badge {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  padding: 10px 15px;
  border-radius: var(--border-radius-md);
  text-align: center;
}

.stat-val {
  font-family: var(--font-title);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-bright);
}

.stat-lbl {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
}