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

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

#game-wrapper {
  position: relative;
  width: 100%;
  max-width: 480px;
  height: 100dvh;
  overflow: hidden;
  background: var(--board-bg);
  border-left: 1px solid var(--border);
  border-right: 1px solid var(--border);
}

#game-canvas {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--board-bg);
}

/* HUD */
#hud {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  padding: 12px 16px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  pointer-events: none;
  z-index: 10;
}

#score-display, #best-display {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

#score-display {
  align-items: flex-start;
}

#best-display {
  align-items: flex-end;
}

.hud-label {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.hud-value {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

#best-value {
  color: var(--accent);
}

/* Overlay base */
.overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background: var(--overlay-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 20;
  padding: 24px;
  gap: 0;
  transition: opacity 0.3s ease;
}

.overlay.hidden {
  display: none;
}

/* Title */
.game-title {
  font-size: clamp(52px, 14vw, 72px);
  font-weight: 900;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, #3B82F6, #8B5CF6, #EC4899);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 8px;
  text-align: center;
}

.game-subtitle {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 40px;
  text-align: center;
  letter-spacing: 0.02em;
}

/* Score card */
.score-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px 32px;
  margin-bottom: 32px;
  text-align: center;
  min-width: 200px;
}

.score-card-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.score-card-value {
  font-size: 42px;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.score-card-value.accent {
  color: var(--accent);
}

.score-card-sub {
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 40px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--btn-bg);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  letter-spacing: 0.01em;
}

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

.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-size: 17px;
  padding: 16px 48px;
}

.btn-primary:active {
  background: #2563eb;
  border-color: #2563eb;
}

.btn-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

/* How to play hint */
.controls-hint {
  margin-top: 24px;
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

.hint-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--text-secondary);
}

.hint-icon {
  font-size: 16px;
}

/* Platform legend */
.platform-legend {
  margin-top: 20px;
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
  color: var(--text-secondary);
}

.legend-dot {
  width: 12px;
  height: 6px;
  border-radius: 3px;
  flex-shrink: 0;
}

.legend-dot.normal { background: #4ade80; }
.legend-dot.moving { background: #60a5fa; }
.legend-dot.breakable { background: #a78060; }

/* Result overlay extras */
#result-overlay .game-title {
  font-size: clamp(38px, 10vw, 52px);
  margin-bottom: 4px;
}

.result-row {
  display: flex;
  gap: 12px;
  margin-bottom: 32px;
}

.result-row .score-card {
  margin-bottom: 0;
  flex: 1;
}

/* Pause indicator */
#pause-btn {
  position: absolute;
  top: 12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--btn-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 12px;
  font-family: inherit;
  padding: 4px 12px;
  cursor: pointer;
  z-index: 15;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

#pause-btn:active {
  background: var(--btn-active);
}

/* Mobile tilt indicator */
#tilt-indicator {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  color: var(--text-muted);
  pointer-events: none;
  z-index: 10;
  opacity: 0;
  transition: opacity 0.5s;
}

#tilt-indicator.visible {
  opacity: 1;
}

#tilt-bar-bg {
  width: 80px;
  height: 4px;
  background: var(--bg-tertiary);
  border-radius: 2px;
  position: relative;
  overflow: hidden;
}

#tilt-bar {
  position: absolute;
  top: 0;
  height: 100%;
  width: 4px;
  background: var(--accent);
  border-radius: 2px;
  left: 50%;
  transform: translateX(-50%);
  transition: left 0.05s;
}