:root {
  --bg-primary: #0D1117;
  --bg-secondary: #161B22;
  --bg-tertiary: #21262D;
  --text-primary: #F0F6FC;
  --text-secondary: #8B949E;
  --text-muted: #484F58;
  --accent: #3B82F6;
  --accent-glow: rgba(59, 130, 246, 0.3);
  --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;
    --accent-glow: rgba(49, 130, 246, 0.2);
    --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%;
  height: 100dvh;
  overflow: hidden;
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Pretendard', 'Segoe UI', Roboto, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  display: flex;
  justify-content: center;
  align-items: stretch;
}

#app {
  width: 100%;
  max-width: 480px;
  height: 100dvh;
  display: flex;
  flex-direction: column;
  position: relative;
  background-color: var(--bg-secondary);
  border-left: 1px solid var(--border);
  border-right: 1px solid var(--border);
}

/* ── Header ── */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background-color: var(--bg-secondary);
  flex-shrink: 0;
}

.score-block {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 80px;
}

.score-label {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 2px;
}

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

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

.header-title {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--text-secondary);
}

/* ── Canvas area ── */
.canvas-wrapper {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  min-height: 0;
}

#gameCanvas {
  display: block;
  background-color: var(--board-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  max-width: 100%;
  max-height: 100%;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

/* ── D-pad ── */
.dpad-wrapper {
  flex-shrink: 0;
  padding: 8px 16px 16px;
  display: flex;
  justify-content: center;
}

.dpad {
  display: grid;
  grid-template-columns: repeat(3, 52px);
  grid-template-rows: repeat(3, 52px);
  gap: 4px;
}

.dpad-btn {
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--btn-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  cursor: pointer;
  font-size: 20px;
  color: var(--text-primary);
  transition: background-color 0.1s, transform 0.1s, border-color 0.1s;
  -webkit-tap-highlight-color: transparent;
}

.dpad-btn:active,
.dpad-btn.pressed {
  background-color: var(--btn-active);
  border-color: var(--accent);
  transform: scale(0.93);
}

.dpad-btn.center {
  background-color: transparent;
  border: none;
  pointer-events: none;
}

.dpad-btn svg {
  width: 22px;
  height: 22px;
  fill: currentColor;
}

/* ── Overlay screens ── */
.overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background-color: var(--overlay-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 10;
  padding: 24px;
  gap: 0;
  transition: opacity 0.25s ease;
}

.overlay.hidden {
  display: none;
}

/* ── Start screen ── */
#startScreen .game-title {
  font-size: 64px;
  font-weight: 900;
  letter-spacing: 0.06em;
  background: linear-gradient(135deg, #3B82F6, #8B5CF6, #EC4899);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 16px;
}

#startScreen .subtitle {
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 48px;
  text-align: center;
}

.start-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  background-color: var(--accent);
  color: #fff;
  border: none;
  border-radius: 14px;
  padding: 16px 48px;
  font-size: 17px;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  box-shadow: 0 0 24px var(--accent-glow);
  transition: transform 0.15s, box-shadow 0.15s;
  -webkit-tap-highlight-color: transparent;
  letter-spacing: 0.03em;
}

.start-btn:active {
  transform: scale(0.96);
  box-shadow: 0 0 12px var(--accent-glow);
}

.start-btn .tap-hint {
  font-size: 12px;
  opacity: 0.75;
  font-weight: 500;
  letter-spacing: 0.04em;
}

/* ── Game over screen ── */
#gameOverScreen .over-title {
  font-size: 40px;
  font-weight: 900;
  letter-spacing: 0.05em;
  color: var(--text-primary);
  margin-bottom: 32px;
}

.over-scores {
  display: flex;
  gap: 24px;
  margin-bottom: 28px;
}

.over-score-block {
  display: flex;
  flex-direction: column;
  align-items: center;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px 28px;
  min-width: 110px;
}

.over-score-block .label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.over-score-block .value {
  font-size: 36px;
  font-weight: 800;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.over-score-block.highlight {
  border-color: var(--accent);
  box-shadow: 0 0 16px var(--accent-glow);
}

.over-score-block.highlight .value {
  color: var(--accent);
}

.new-record-badge {
  font-size: 12px;
  font-weight: 700;
  color: #EC4899;
  letter-spacing: 0.08em;
  margin-bottom: 28px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.new-record-badge.hidden {
  display: none;
}

.new-record-badge::before {
  content: '★';
  font-size: 14px;
}

.retry-btn {
  background-color: var(--accent);
  color: #fff;
  border: none;
  border-radius: 14px;
  padding: 14px 44px;
  font-size: 16px;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  box-shadow: 0 0 20px var(--accent-glow);
  transition: transform 0.15s, box-shadow 0.15s;
  -webkit-tap-highlight-color: transparent;
  letter-spacing: 0.03em;
}

.retry-btn:active {
  transform: scale(0.96);
  box-shadow: 0 0 10px var(--accent-glow);
}