:root {
  --bg-primary: #0D1117;
  --bg-secondary: #161B22;
  --bg-tertiary: #21262D;
  --text-primary: #F0F6FC;
  --text-secondary: #8B949E;
  --text-muted: #484F58;
  --accent: #3B82F6;
  --border: #30363D;
  --btn-bg: #21262D;
  --btn-active: #30363D;
  --overlay-bg: rgba(0, 0, 0, 0.85);
  --board-bg: #0A0E14;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg-primary: #FFFFFF;
    --bg-secondary: #F6F8FA;
    --bg-tertiary: #E9ECF0;
    --text-primary: #1B1E28;
    --text-secondary: #57606A;
    --text-muted: #8C959F;
    --accent: #3182F6;
    --border: #D0D7DE;
    --btn-bg: #E9ECF0;
    --btn-active: #D0D7DE;
    --overlay-bg: rgba(255, 255, 255, 0.9);
    --board-bg: #F0F2F5;
  }
}

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

html, body {
  height: 100%;
  width: 100%;
  overflow: hidden;
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, 'Pretendard', 'Segoe UI', Roboto, sans-serif;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

#app {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100dvh;
  position: relative;
  background: var(--bg-primary);
}

#game-wrapper {
  position: relative;
  width: 100%;
  max-width: 480px;
  height: 100dvh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* HUD */
#hud {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 16px;
  background: linear-gradient(to bottom, rgba(0,0,0,0.5) 0%, transparent 100%);
  pointer-events: none;
}

@media (prefers-color-scheme: light) {
  #hud {
    background: linear-gradient(to bottom, rgba(255,255,255,0.6) 0%, transparent 100%);
  }
}

.hud-score {
  font-size: 28px;
  font-weight: 800;
  color: var(--text-primary);
  text-shadow: 0 1px 4px rgba(0,0,0,0.5);
  letter-spacing: -0.5px;
}

.hud-coins {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 18px;
  font-weight: 700;
  color: #F59E0B;
  text-shadow: 0 1px 4px rgba(0,0,0,0.5);
}

.hud-best {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  text-shadow: 0 1px 4px rgba(0,0,0,0.5);
}

/* Canvas */
#gameCanvas {
  display: block;
  width: 100%;
  max-width: 480px;
  height: 100dvh;
  background: var(--board-bg);
  touch-action: none;
}

/* Overlays */
.overlay {
  position: absolute;
  inset: 0;
  z-index: 20;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0;
  background: var(--overlay-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.overlay.visible {
  opacity: 1;
  pointer-events: all;
}

/* Start Screen */
#start-screen {
  gap: 0;
}

.game-title {
  font-size: clamp(52px, 18vw, 80px);
  font-weight: 900;
  letter-spacing: -2px;
  background: linear-gradient(135deg, #3B82F6 0%, #8B5CF6 40%, #EC4899 80%, #F59E0B 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-align: center;
  line-height: 1;
  margin-bottom: 6px;
  filter: drop-shadow(0 2px 8px rgba(59,130,246,0.4));
}

.game-subtitle {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin-bottom: 48px;
}

.character-preview {
  font-size: 64px;
  margin-bottom: 40px;
  animation: bounce-preview 1.2s ease-in-out infinite;
}

@keyframes bounce-preview {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-12px) scale(1.05); }
}

.best-score-display {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

.best-score-display .score-value {
  font-weight: 700;
  color: #F59E0B;
  font-size: 16px;
}

/* Buttons */
.btn-primary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 14px;
  padding: 16px 40px;
  font-size: 18px;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  letter-spacing: -0.2px;
  transition: transform 0.1s, box-shadow 0.1s, background 0.15s;
  box-shadow: 0 4px 16px rgba(59,130,246,0.35);
  min-width: 180px;
  margin-bottom: 12px;
}

.btn-primary:active {
  transform: scale(0.96);
  box-shadow: 0 2px 8px rgba(59,130,246,0.25);
}

.btn-secondary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--btn-bg);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 13px 32px;
  font-size: 15px;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  letter-spacing: -0.2px;
  transition: transform 0.1s, background 0.15s;
  min-width: 180px;
}

.btn-secondary:active {
  transform: scale(0.96);
  background: var(--btn-active);
}

/* Game Over Screen */
#gameover-screen {
  gap: 0;
}

.gameover-title {
  font-size: 36px;
  font-weight: 900;
  color: var(--text-primary);
  letter-spacing: -1px;
  margin-bottom: 4px;
}

.gameover-icon {
  font-size: 56px;
  margin-bottom: 28px;
  animation: shake-once 0.5s ease;
}

@keyframes shake-once {
  0%, 100% { transform: rotate(0deg); }
  20% { transform: rotate(-10deg); }
  40% { transform: rotate(10deg); }
  60% { transform: rotate(-6deg); }
  80% { transform: rotate(6deg); }
}

.score-cards {
  display: flex;
  gap: 12px;
  margin-bottom: 36px;
}

.score-card {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 20px;
  text-align: center;
  min-width: 100px;
}

.score-card-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 4px;
}

.score-card-value {
  font-size: 28px;
  font-weight: 800;
  color: var(--text-primary);
}

.score-card-value.gold {
  color: #F59E0B;
}

.score-card-value.new-best {
  color: #10B981;
  animation: pulse-best 0.8s ease infinite alternate;
}

@keyframes pulse-best {
  from { transform: scale(1); }
  to { transform: scale(1.08); }
}

.new-record-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: linear-gradient(135deg, #F59E0B, #EF4444);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.5px;
  padding: 4px 10px;
  border-radius: 20px;
  margin-bottom: 24px;
  animation: scale-in 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes scale-in {
  from { transform: scale(0); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.new-record-badge.hidden {
  visibility: hidden;
}

/* Mobile Controls */
#mobile-controls {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 15;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 10px 16px 16px;
  pointer-events: none;
}

#mobile-controls.hidden {
  display: none;
}

.ctrl-row {
  display: flex;
  gap: 6px;
  pointer-events: all;
}

.ctrl-btn {
  width: 52px;
  height: 52px;
  background: var(--btn-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  cursor: pointer;
  opacity: 0.75;
  transition: opacity 0.1s, transform 0.1s, background 0.1s;
  touch-action: manipulation;
}

.ctrl-btn:active {
  opacity: 1;
  transform: scale(0.92);
  background: var(--btn-active);
}

/* Pause button */
#pause-btn {
  position: absolute;
  top: 12px;
  right: 16px;
  z-index: 15;
  width: 36px;
  height: 36px;
  background: var(--btn-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  cursor: pointer;
  opacity: 0.8;
  transition: opacity 0.1s;
}

#pause-btn:active { opacity: 1; }
#pause-btn.hidden { display: none; }

/* Pause screen */
#pause-screen .pause-title {
  font-size: 32px;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 8px;
}

#pause-screen .pause-score {
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

/* Idle warning */
#idle-warning {
  position: absolute;
  bottom: 130px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 12;
  background: rgba(239,68,68,0.9);
  color: #fff;
  border-radius: 20px;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 700;
  white-space: nowrap;
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}

#idle-warning.visible {
  opacity: 1;
  animation: pulse-warning 0.6s ease infinite alternate;
}

@keyframes pulse-warning {
  from { background: rgba(239,68,68,0.9); }
  to { background: rgba(239,68,68,1); transform: translateX(-50%) scale(1.03); }
}

/* Coin popup */
.coin-popup {
  position: absolute;
  font-size: 14px;
  font-weight: 700;
  color: #F59E0B;
  pointer-events: none;
  z-index: 11;
  animation: float-up 0.8s ease forwards;
  text-shadow: 0 1px 4px rgba(0,0,0,0.5);
}

@keyframes float-up {
  0% { opacity: 1; transform: translateY(0) scale(1); }
  100% { opacity: 0; transform: translateY(-40px) scale(1.2); }
}

/* Responsive adjustments */
@media (max-height: 600px) {
  .ctrl-btn {
    width: 44px;
    height: 44px;
    font-size: 18px;
  }
  #mobile-controls {
    padding: 6px 12px 8px;
    gap: 4px;
  }
}