*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #0f0f1a;
  --bg-secondary: #1a1a2e;
  --bg-card: #16213e;
  --text-primary: #e8e8f0;
  --text-secondary: #9a9ab0;
  --accent-x: #ff6b6b;
  --accent-o: #4ecdc4;
  --accent-glow-x: rgba(255, 107, 107, 0.3);
  --accent-glow-o: rgba(78, 205, 196, 0.3);
  --accent-win: #ffd93d;
  --accent-win-bg: rgba(255, 217, 61, 0.12);
  --cell-border: #2a2a4a;
  --cell-hover: #1e2a45;
  --btn-primary: #4ecdc4;
  --btn-primary-hover: #45b7aa;
  --btn-secondary: #2a2a4a;
  --btn-secondary-hover: #3a3a5a;
  --radius: 16px;
  --radius-sm: 10px;
}

body {
  font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.container {
  width: 100%;
  max-width: 420px;
  padding: 32px 24px;
  background: var(--bg-secondary);
  border-radius: 28px;
  border: 1px solid rgba(255, 255, 255, 0.05);
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.5);
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

.header h1 {
  font-size: 1.6rem;
  font-weight: 700;
  background: linear-gradient(135deg, #ff6b6b, #4ecdc4);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.turn-indicator {
  display: flex;
  align-items: center;
  gap: 10px;
}

.turn-label {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.turn-badge {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 700;
  border-radius: 50%;
  background: var(--bg-card);
  transition: all 0.3s ease;
}

.turn-badge.x-turn {
  color: var(--accent-x);
  box-shadow: 0 0 16px var(--accent-glow-x);
  border: 2px solid var(--accent-x);
}

.turn-badge.o-turn {
  color: var(--accent-o);
  box-shadow: 0 0 16px var(--accent-glow-o);
  border: 2px solid var(--accent-o);
}

.scoreboard {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 28px;
}

.score-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 12px 8px;
  background: var(--bg-card);
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 255, 255, 0.04);
  transition: transform 0.2s ease;
}

.score-item:hover {
  transform: translateY(-2px);
}

.score-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.score-value {
  font-size: 1.5rem;
  font-weight: 700;
}

.x-score .score-value { color: var(--accent-x); }
.o-score .score-value { color: var(--accent-o); }
.draws .score-value { color: var(--text-secondary); }

.game-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 24px;
  aspect-ratio: 1;
}

.cell {
  background: var(--bg-card);
  border: 1px solid var(--cell-border);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.8rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  aspect-ratio: 1;
  position: relative;
  overflow: hidden;
}

.cell::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at center, rgba(255,255,255,0.03), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.cell:hover:not(.taken):not(.winning)::before {
  opacity: 1;
}

.cell:hover:not(.taken):not(.winning) {
  border-color: rgba(255, 255, 255, 0.15);
  background: var(--cell-hover);
  transform: scale(1.02);
}

.cell.taken {
  cursor: default;
}

.cell.taken:hover {
  transform: none;
  border-color: var(--cell-border);
}

.cell.x-move {
  color: var(--accent-x);
  text-shadow: 0 0 20px var(--accent-glow-x);
}

.cell.o-move {
  color: var(--accent-o);
  text-shadow: 0 0 20px var(--accent-glow-o);
}

.cell.winning {
  background: var(--accent-win-bg);
  border-color: var(--accent-win);
  animation: pulse 1s ease-in-out infinite;
}

.cell.winning.x-move {
  color: var(--accent-win);
  text-shadow: 0 0 30px rgba(255, 217, 61, 0.5);
}

.cell.winning.o-move {
  color: var(--accent-win);
  text-shadow: 0 0 30px rgba(255, 217, 61, 0.5);
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.04); }
}

@keyframes popIn {
  0% { transform: scale(0); opacity: 0; }
  50% { transform: scale(1.2); }
  100% { transform: scale(1); opacity: 1; }
}

.cell.animate-in {
  animation: popIn 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
}

.status-message {
  text-align: center;
  font-size: 1rem;
  font-weight: 500;
  padding: 12px;
  margin-bottom: 20px;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.04);
  transition: all 0.3s ease;
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.status-message.x-turn {
  color: var(--accent-x);
  border-color: var(--accent-glow-x);
}

.status-message.o-turn {
  color: var(--accent-o);
  border-color: var(--accent-glow-o);
}

.status-message.win {
  color: var(--accent-win);
  border-color: rgba(255, 217, 61, 0.3);
  background: var(--accent-win-bg);
}

.status-message.draw {
  color: var(--text-secondary);
  border-color: rgba(255, 255, 255, 0.1);
}

.actions {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
}

.btn {
  flex: 1;
  padding: 12px 20px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  letter-spacing: 0.02em;
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  background: var(--btn-primary);
  color: #0f0f1a;
}

.btn-primary:hover {
  background: var(--btn-primary-hover);
  box-shadow: 0 4px 20px rgba(78, 205, 196, 0.3);
}

.btn-secondary {
  background: var(--btn-secondary);
  color: var(--text-secondary);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.btn-secondary:hover {
  background: var(--btn-secondary-hover);
  color: var(--text-primary);
}

.footer {
  text-align: center;
}

.footer p {
  font-size: 0.75rem;
  color: var(--text-secondary);
  opacity: 0.6;
}

/* Responsive */
@media (max-width: 480px) {
  .container {
    padding: 24px 16px;
  }

  .header h1 {
    font-size: 1.3rem;
  }

  .cell {
    font-size: 2.2rem;
  }

  .score-value {
    font-size: 1.2rem;
  }
}