: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;
  }
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

html, body {
  height: 100%;
  width: 100%;
  overflow: hidden;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Pretendard', 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100dvh;
  user-select: none;
}

#app {
  width: 100%;
  max-width: 480px;
  height: 100dvh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  position: relative;
  background: var(--bg-secondary);
  overflow: hidden;
}

/* Header */
.header {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.header-title {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 3px;
  background: linear-gradient(135deg, #FFD700, #FF8C00, #FF4500);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-stats {
  display: flex;
  gap: 16px;
  align-items: center;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1px;
}

.stat-label {
  font-size: 9px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
}

.stat-value {
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
}

.lives-display {
  display: flex;
  gap: 3px;
  align-items: center;
}

.life-icon {
  width: 14px;
  height: 14px;
  background: #FFD700;
  border-radius: 50% 50% 50% 0;
  transform: rotate(45deg);
  transition: opacity 0.3s;
}

.life-icon.lost {
  opacity: 0.2;
}

/* Game canvas area */
.canvas-wrapper {
  flex: 1;
  width: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  background: var(--board-bg);
  position: relative;
  overflow: hidden;
}

#gameCanvas {
  display: block;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

/* Controls */
.controls {
  width: 100%;
  padding: 10px 16px 16px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.dpad {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(3, 1fr);
  gap: 4px;
  width: 128px;
  height: 128px;
  margin: 0 auto;
}

.dpad-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--btn-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  font-size: 18px;
  color: var(--text-secondary);
  transition: background 0.1s, transform 0.1s, border-color 0.1s;
  -webkit-tap-highlight-color: transparent;
}

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

.dpad-btn.center {
  background: var(--bg-tertiary);
  border-color: var(--border);
  cursor: default;
}

.dpad-btn:nth-child(1) { grid-area: 1 / 2; }
.dpad-btn:nth-child(2) { grid-area: 2 / 1; }
.dpad-btn.center { grid-area: 2 / 2; }
.dpad-btn:nth-child(4) { grid-area: 2 / 3; }
.dpad-btn:nth-child(5) { grid-area: 3 / 2; }

/* Overlay screens */
.overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--overlay-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 100;
  padding: 24px;
  gap: 0;
  transition: opacity 0.3s;
}

.overlay.hidden {
  display: none;
}

.overlay-icon {
  font-size: 56px;
  margin-bottom: 8px;
  animation: bounce 1.2s infinite;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.overlay-title {
  font-size: 32px;
  font-weight: 800;
  letter-spacing: 6px;
  text-transform: uppercase;
  background: linear-gradient(135deg, #FFD700, #FF8C00, #FF4500);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 6px;
  text-align: center;
}

.overlay-subtitle {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 24px;
  text-align: center;
  letter-spacing: 0.5px;
}

.overlay-score-row {
  width: 100%;
  max-width: 260px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 16px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 8px;
  margin-bottom: 6px;
  font-size: 13px;
}

.overlay-score-row .label {
  color: var(--text-secondary);
}

.overlay-score-row .value {
  font-weight: 700;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
}

.overlay-score-row .value.highlight {
  color: #FFD700;
}

.btn-primary {
  margin-top: 20px;
  padding: 12px 40px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.5px;
  cursor: pointer;
  transition: filter 0.15s, transform 0.15s;
  font-family: inherit;
}

.btn-primary:hover {
  filter: brightness(1.12);
}

.btn-primary:active {
  transform: scale(0.96);
}

.btn-secondary {
  margin-top: 10px;
  padding: 10px 32px;
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  font-family: inherit;
}

.btn-secondary:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

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

/* How to play tips */
.tips {
  margin-top: 16px;
  width: 100%;
  max-width: 260px;
}

.tips-title {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--text-muted);
  margin-bottom: 8px;
  text-align: center;
}

.tip-row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 0;
  font-size: 12px;
  color: var(--text-secondary);
}

.tip-icon {
  font-size: 14px;
  width: 20px;
  text-align: center;
  flex-shrink: 0;
}

/* Level clear animation */
.level-flash {
  animation: levelFlash 0.4s ease-in-out infinite alternate;
}

@keyframes levelFlash {
  from { opacity: 1; }
  to { opacity: 0.3; }
}

/* Score popup */
.score-popup {
  position: absolute;
  font-size: 13px;
  font-weight: 700;
  color: #FFD700;
  pointer-events: none;
  animation: scoreFloat 0.9s ease-out forwards;
  z-index: 50;
  text-shadow: 0 1px 3px rgba(0,0,0,0.6);
}

@keyframes scoreFloat {
  0% { opacity: 1; transform: translateY(0) scale(1); }
  100% { opacity: 0; transform: translateY(-36px) scale(0.7); }
}

/* Responsive */
@media (max-height: 650px) {
  .header { padding: 8px 16px; }
  .controls { padding: 6px 16px 10px; }
  .dpad { width: 108px; height: 108px; }
}

@media (max-height: 560px) {
  .dpad { width: 90px; height: 90px; }
  .dpad-btn { font-size: 14px; }
  .controls { padding: 4px 16px 6px; }
}