/* CSS Custom Properties for theming */
:root {
  --primary-color: #667eea;
  --primary-dark: #5a6fd8;
  --secondary-color: #764ba2;
  --accent-color: #f093fb;
  --success-color: #4ecdc4;
  --warning-color: #fce38a;
  --danger-color: #ff6b6b;
  --dark-color: #2c3e50;
  --light-color: #ecf0f1;
  --white: #ffffff;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
  --border-radius: 12px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset and base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  color: var(--dark-color);
}

/* Container */
.container {
  background: var(--white);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
  padding: 2rem;
  width: 100%;
  max-width: 500px;
  text-align: center;
}

/* Header */
.game-header {
  margin-bottom: 2rem;
}

.game-title {
  font-size: 2.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
}

.game-subtitle {
  color: #666;
  font-size: 1rem;
  font-weight: 300;
}

/* Game Info */
.game-info {
  margin-bottom: 2rem;
}

.score-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.score-item {
  background: linear-gradient(135deg, #f8f9fa, #e9ecef);
  padding: 1rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.score-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.score-label {
  display: block;
  font-size: 0.875rem;
  color: #666;
  margin-bottom: 0.25rem;
  font-weight: 400;
}

.score-value {
  display: block;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.game-status {
  background: linear-gradient(135deg, var(--accent-color), var(--primary-color));
  color: var(--white);
  padding: 0.75rem 1.5rem;
  border-radius: 25px;
  font-weight: 600;
  box-shadow: var(--shadow);
}

/* Game Board */
.game-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
  margin-bottom: 2rem;
  background: #f8f9fa;
  padding: 1rem;
  border-radius: var(--border-radius);
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.cell {
  aspect-ratio: 1;
  background: var(--white);
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.cell:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  background: linear-gradient(135deg, #fff, #f8f9fa);
}

.cell:active {
  transform: translateY(0);
}

.cell.x {
  color: var(--danger-color);
  background: linear-gradient(135deg, #fff5f5, #fed7d7);
}

.cell.o {
  color: var(--success-color);
  background: linear-gradient(135deg, #f0fff4, #c6f6d5);
}

.cell.winning {
  animation: pulse 0.6s ease-in-out;
  background: linear-gradient(135deg, var(--warning-color), #ffd93d);
  color: var(--dark-color);
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

/* Buttons */
.game-controls {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 25px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 120px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: var(--white);
  box-shadow: var(--shadow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: linear-gradient(135deg, #6c757d, #5a6268);
  color: var(--white);
  box-shadow: var(--shadow);
}

.btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn:active {
  transform: translateY(0);
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(5px);
  z-index: 1000;
  animation: fadeIn 0.3s ease-out;
}

.modal.show {
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-content {
  background: var(--white);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
  max-width: 400px;
  width: 90%;
  margin: 1rem;
  animation: slideIn 0.3s ease-out;
}

.modal-header {
  padding: 1.5rem 1.5rem 0;
}

.modal-header h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--dark-color);
}

.modal-body {
  padding: 1rem 1.5rem;
}

.modal-body p {
  font-size: 1.1rem;
  color: #666;
  line-height: 1.5;
}

.modal-footer {
  padding: 0 1.5rem 1.5rem;
  text-align: center;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateY(-20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    padding: 1.5rem;
    margin: 0.5rem;
  }
  
  .game-title {
    font-size: 2rem;
  }
  
  .score-board {
    gap: 0.75rem;
  }
  
  .score-item {
    padding: 0.75rem;
  }
  
  .score-value {
    font-size: 1.25rem;
  }
  
  .cell {
    font-size: 2rem;
  }
  
  .game-controls {
    flex-direction: column;
    align-items: center;
  }
  
  .btn {
    width: 100%;
    max-width: 200px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 1rem;
  }
  
  .game-title {
    font-size: 1.75rem;
  }
  
  .game-subtitle {
    font-size: 0.875rem;
  }
  
  .score-board {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }
  
  .score-item {
    padding: 0.5rem;
  }
  
  .score-label {
    font-size: 0.75rem;
  }
  
  .score-value {
    font-size: 1.125rem;
  }
  
  .game-board {
    gap: 0.5rem;
    padding: 0.75rem;
  }
  
  .cell {
    font-size: 1.75rem;
  }
  
  .game-status {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
  }
}

/* Accessibility improvements */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Focus styles for keyboard navigation */
.cell:focus,
.btn:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 4px 8px rgba(0, 0, 0, 0.3);
  }
}