/* ==========================================================================
   Cyber Pong 2D - Design Tokens & Stylesheet
   ========================================================================== */

:root {
  /* Color Palette - Midnight Neon Cyber Theme */
  --color-bg-primary: #0a0e17;
  --color-bg-surface: rgba(16, 24, 40, 0.85);
  --color-border-glow: rgba(0, 255, 255, 0.4);
  --color-player-cyan: #00ffff;
  --color-ai-magenta: #ff007f;
  --color-ball-white: #ffffff;
  --color-accent-green: #00ff88;
  --color-accent-amber: #ffaa00;
  --color-text-primary: #f0f6fc;
  --color-text-secondary: #8b949e;
  --color-focus-ring: #00ffff;

  /* Glow Effects */
  --glow-cyan: 0 0 12px rgba(0, 255, 255, 0.6);
  --glow-magenta: 0 0 12px rgba(255, 0, 127, 0.6);
  --glow-ball: 0 0 16px rgba(255, 255, 255, 0.9);
  --glow-text: 0 0 10px rgba(0, 255, 255, 0.7);

  /* Typography */
  --font-family-display: 'Orbitron', system-ui, -apple-system, sans-serif;
  --font-family-body: 'Inter', system-ui, -apple-system, sans-serif;

  /* Transitions & Radii */
  --transition-fast: 150ms ease-out;
  --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --touch-target-min: 44px;
}

/* Reset and Base Layout */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  width: 100%;
  height: 100%;
  background-color: var(--color-bg-primary);
  color: var(--color-text-primary);
  font-family: var(--font-family-body);
  overflow: hidden;
  display: flex;
  justify-content: center;
  align-items: center;
  user-select: none;
  -webkit-user-select: none;
}

/* Screen reader utility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Main Container Wrapper */
.game-wrapper {
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 16px;
  background: radial-gradient(circle at center, rgba(16, 28, 54, 0.5) 0%, var(--color-bg-primary) 70%);
}

.game-container {
  width: 100%;
  max-width: 1000px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

/* Header & HUD Section */
.hud-header {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 20px;
  background: var(--color-bg-surface);
  border: 1px solid rgba(0, 255, 255, 0.2);
  border-radius: var(--radius-md);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
  backdrop-filter: blur(8px);
}

.hud-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hud-label {
  font-family: var(--font-family-display);
  font-size: clamp(0.7rem, 1vw, 0.85rem);
  font-weight: 800;
  letter-spacing: 0.1em;
  color: var(--color-text-secondary);
}

.player-score-box .hud-label {
  color: var(--color-player-cyan);
}

.ai-score-box .hud-label {
  color: var(--color-ai-magenta);
}

.score-digit {
  font-family: var(--font-family-display);
  font-size: clamp(2.0rem, 4vw, 3.0rem);
  font-weight: 900;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  display: inline-block;
  transition: transform var(--transition-fast), color var(--transition-fast);
}

.score-digit.score-bounce-player {
  animation: scoreBouncePlayer 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.score-digit.score-bounce-ai {
  animation: scoreBounceAi 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes scoreBouncePlayer {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.35);
    color: #ffffff;
    text-shadow: 0 0 20px #00ffff, 0 0 35px #00ffff;
  }
  100% {
    transform: scale(1);
  }
}

@keyframes scoreBounceAi {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.35);
    color: #ffffff;
    text-shadow: 0 0 20px #ff007f, 0 0 35px #ff007f;
  }
  100% {
    transform: scale(1);
  }
}

.player-score-box .score-digit {
  color: var(--color-player-cyan);
  text-shadow: var(--glow-cyan);
}

.ai-score-box .score-digit {
  color: var(--color-ai-magenta);
  text-shadow: var(--glow-magenta);
}

/* Rally Speed Meter */
.rally-meter-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  min-width: 140px;
}

.rally-meter-bar {
  width: 100%;
  height: 8px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 4px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.rally-meter-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-player-cyan), var(--color-accent-green), var(--color-accent-amber), var(--color-ai-magenta));
  transition: width var(--transition-fast);
}

.rally-value {
  font-family: var(--font-family-display);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--color-accent-green);
}

/* Header Controls */
.hud-controls {
  display: flex;
  gap: 8px;
}

/* Buttons and Interactive Elements */
.btn-icon {
  min-width: var(--touch-target-min);
  min-height: var(--touch-target-min);
  display: inline-flex;
  justify-content: center;
  align-items: center;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(0, 255, 255, 0.3);
  border-radius: var(--radius-sm);
  color: var(--color-text-primary);
  font-size: 1.2rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-icon:hover {
  background: rgba(0, 255, 255, 0.15);
  border-color: var(--color-player-cyan);
  box-shadow: var(--glow-cyan);
  transform: translateY(-1px);
}

.btn-icon:active {
  transform: translateY(1px);
}

.btn-icon:focus-visible,
.btn-pill:focus-visible,
.btn-cta:focus-visible,
.btn-secondary:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
  box-shadow: var(--glow-cyan);
}

/* Canvas Arena Viewport (Responsive 16:9) */
.canvas-arena-container {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  max-width: 1000px;
  background-color: #050811;
  border: 2px solid rgba(0, 255, 255, 0.3);
  border-radius: var(--radius-md);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.7), inset 0 0 20px rgba(0, 255, 255, 0.05);
  overflow: hidden;
  display: flex;
  justify-content: center;
  align-items: center;
}

#pong-canvas {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
}

/* Modal Overlays */
.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(8px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 10;
  transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

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

.modal-card {
  width: 90%;
  max-width: 480px;
  padding: 28px 24px;
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border-glow);
  border-radius: var(--radius-lg);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.8), var(--glow-cyan);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 18px;
}

.game-title {
  font-family: var(--font-family-display);
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  font-weight: 900;
  letter-spacing: 0.08em;
  color: var(--color-player-cyan);
  text-shadow: var(--glow-cyan);
  margin-bottom: -10px;
}

.game-subtitle {
  font-family: var(--font-family-display);
  font-size: 0.8rem;
  letter-spacing: 0.25em;
  color: var(--color-text-secondary);
}

.modal-title {
  font-family: var(--font-family-display);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--color-text-primary);
}

.text-glow {
  text-shadow: var(--glow-cyan);
}

.final-score-text {
  font-family: var(--font-family-display);
  font-size: 3rem;
  font-weight: 900;
  letter-spacing: 0.05em;
  color: var(--color-ball-white);
  text-shadow: var(--glow-ball);
}

.gameover-subtitle {
  font-family: var(--font-family-display);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-accent-green);
  letter-spacing: 0.1em;
}

/* Control Groups */
.control-group {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.group-label {
  font-family: var(--font-family-display);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-text-secondary);
}

.difficulty-pill-group {
  display: flex;
  width: 100%;
  gap: 8px;
  justify-content: center;
}

.btn-pill {
  flex: 1;
  min-height: var(--touch-target-min);
  padding: 8px 12px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-sm);
  color: var(--color-text-secondary);
  font-family: var(--font-family-display);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-pill:hover {
  background: rgba(0, 255, 255, 0.1);
  color: var(--color-text-primary);
  border-color: rgba(0, 255, 255, 0.4);
}

.btn-pill.active {
  background: rgba(0, 255, 255, 0.2);
  border-color: var(--color-player-cyan);
  color: var(--color-player-cyan);
  box-shadow: var(--glow-cyan);
}

/* Controls Legend */
.controls-legend {
  width: 100%;
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.legend-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
}

.legend-key {
  font-family: var(--font-family-display);
  font-weight: 700;
  color: var(--color-player-cyan);
  background: rgba(0, 255, 255, 0.1);
  padding: 2px 6px;
  border-radius: 4px;
}

.legend-desc {
  color: var(--color-text-secondary);
}

/* Action CTA Buttons */
.btn-cta {
  width: 100%;
  min-height: var(--touch-target-min);
  padding: 12px 24px;
  background: linear-gradient(135deg, rgba(0, 255, 255, 0.3), rgba(0, 255, 136, 0.3));
  border: 1px solid var(--color-player-cyan);
  border-radius: var(--radius-sm);
  color: #ffffff;
  font-family: var(--font-family-display);
  font-size: 1.0rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  cursor: pointer;
  box-shadow: var(--glow-cyan);
  transition: all var(--transition-fast);
}

.btn-cta:hover {
  background: linear-gradient(135deg, rgba(0, 255, 255, 0.5), rgba(0, 255, 136, 0.5));
  box-shadow: 0 0 20px rgba(0, 255, 255, 0.8);
  transform: translateY(-2px);
}

.btn-cta:active {
  transform: translateY(1px);
}

.btn-secondary {
  width: 100%;
  min-height: var(--touch-target-min);
  padding: 10px 20px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-sm);
  color: var(--color-text-secondary);
  font-family: var(--font-family-display);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-secondary:hover {
  background: rgba(255, 0, 127, 0.15);
  border-color: var(--color-ai-magenta);
  color: var(--color-text-primary);
  box-shadow: var(--glow-magenta);
}

.modal-actions {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 10px;
}