:root {
  --color-bg-primary:     #0f0f23;
  --color-bg-surface:     #1a1a35;
  --color-bg-overlay:     rgba(0, 0, 0, 0.80);
  --color-border:         #6262a2;
  --color-border-accent:  #7070b0;
  --color-text-primary:   #e0e0ff;
  --color-text-accent:    #00d4ff;
  --color-text-muted:     #8888bb;
  --color-text-error:     #ff4444;
  --color-success:        #66FF66;
  --color-warning:        #FFE600;
  --color-error:          #FF4444;
  --color-piece-I:        #00E5FF;
  --color-piece-O:        #FFE600;
  --color-piece-T:        #CC66FF;
  --color-piece-S:        #66FF66;
  --color-piece-Z:        #FF4444;
  --color-piece-J:        #4488FF;
  --color-piece-L:        #FF9933;
  --color-grid-line:      rgba(255, 255, 255, 0.05);
  --color-flash:          rgba(255, 255, 255, 0.50);
  --font-ui:              'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono:            'Cascadia Code', 'Fira Code', 'Consolas', monospace;
  --font-heading:         'Orbitron', var(--font-ui);
  --font-size-xs:         0.75rem;
  --font-size-sm:         0.875rem;
  --font-size-base:       1rem;
  --font-size-lg:         1.5rem;
  --font-size-xl:         2rem;
  --font-size-2xl:        3rem;
  --font-weight-normal:   400;
  --font-weight-bold:     700;
  --line-height-tight:    1.1;
  --line-height-normal:   1.5;
  --letter-spacing-label: 0.1em;
  --space-1:              4px;
  --space-2:              8px;
  --space-3:              12px;
  --space-4:              16px;
  --space-5:              20px;
  --space-6:              24px;
  --space-8:              32px;
  --space-12:             48px;
  --cell-size:            32px;
  --panel-width:          160px;
  --layout-gap:           var(--space-5);
  --radius-sm:            3px;
  --radius-md:            8px;
  --radius-lg:            12px;
  --shadow-sm:            0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md:            0 4px 12px rgba(0, 0, 0, 0.5);
  --shadow-lg:            0 8px 32px rgba(0, 0, 0, 0.7);
  --transition-fast:      150ms ease;
  --transition-normal:    300ms ease;
  --transition-slow:      500ms ease;
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --transition-fast:    0ms;
    --transition-normal:  0ms;
    --transition-slow:    0ms;
  }
}

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

/* --- Body --- */
body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: radial-gradient(ellipse at center, #0f0f23 0%, #080816 100%);
  color: var(--color-text-primary);
  font-family: var(--font-ui);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  opacity: 0.35;
  background: radial-gradient(ellipse at 30% 50%, currentColor, transparent 70%);
  color: var(--color-text-accent);
  animation: bg-drift 25s ease-in-out infinite alternate;
  pointer-events: none;
}

@keyframes bg-drift {
  from { transform: translate(-10%, -10%) scale(1.2); }
  to   { transform: translate(10%, 10%) scale(1.2); }
}

/* --- Game Container (CSS Grid) --- */
#game-container {
  display: grid;
  grid-template-columns: var(--panel-width) calc(var(--cell-size) * 12) var(--panel-width);
  gap: var(--layout-gap);
  position: relative;
  padding: var(--space-4);
}

/* --- Panels --- */
#stats-panel,
#right-panel {
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  box-shadow: 0 0 20px rgba(0, 100, 180, 0.06);
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.label {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: var(--letter-spacing-label);
}

.value {
  font-family: var(--font-mono);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-accent);
  line-height: var(--line-height-tight);
}

/* --- Score Pop Animation --- */
#score-value {
  transition: transform var(--transition-fast);
  display: inline-block;
}

.score-pop {
  transform: scale(1.15);
}

/* --- Canvas Elements --- */
#game-canvas,
#next-canvas,
#hold-canvas {
  border: 2px solid var(--color-border-accent);
  border-radius: var(--radius-sm);
  max-width: 100%;
  height: auto;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

#game-canvas {
  box-shadow: 0 0 15px rgba(0, 212, 255, 0.1), 0 0 30px rgba(0, 212, 255, 0.05);
  outline: 2px solid var(--color-border);
  outline-offset: 3px;
}

#game-canvas:focus {
  outline: 2px solid var(--color-text-accent);
  outline-offset: 2px;
}

/* --- Hold / Next Piece Sections --- */
.hold-piece-section,
.next-piece-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  align-items: center;
}

.hold-piece-section .label,
.next-piece-section .label {
  align-self: flex-start;
}

.hold-piece-section canvas {
  opacity: 1;
  transition: opacity var(--transition-fast);
}

.hold-piece-section canvas.hold-used {
  opacity: 0.4;
}

/* --- Sound Toggle --- */
#sound-toggle {
  font-family: var(--font-ui);
  font-size: var(--font-size-xs);
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-3);
  cursor: pointer;
  width: 100%;
  text-align: center;
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

#sound-toggle:hover {
  background-color: var(--color-border);
  border-color: var(--color-border-accent);
}

#sound-toggle:focus-visible {
  outline: 2px solid var(--color-text-accent);
  outline-offset: 2px;
}

/* --- Controls Legend --- */
#controls-panel {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.control-row {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--space-1);
  flex-wrap: wrap;
}

kbd {
  display: inline-block;
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: var(--space-1) var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--font-size-xs);
  color: var(--color-text-primary);
  box-shadow: var(--shadow-sm);
  line-height: 1;
}

/* --- Overlays --- */
.overlay {
  position: absolute;
  inset: 0;
  background: var(--color-bg-overlay);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 10;
  opacity: 1;
  visibility: visible;
  transform: scale(1);
  transition: opacity var(--transition-normal), visibility var(--transition-normal), transform var(--transition-normal);
  text-align: center;
  padding: var(--space-4);
  border-radius: var(--radius-md);
  overflow-y: auto;
}

.overlay.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: scale(0.95);
}

.overlay-title {
  font-family: var(--font-heading);
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-accent);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-6);
  letter-spacing: 0.2em;
}

.overlay-title span {
  display: inline-block;
  text-shadow: 0 0 10px currentColor, 0 0 30px currentColor, 0 0 60px currentColor;
  animation: title-glow 2.5s ease-in-out infinite alternate;
}

.overlay-title span:nth-child(2) { animation-delay: 0.15s; }
.overlay-title span:nth-child(3) { animation-delay: 0.3s; }
.overlay-title span:nth-child(4) { animation-delay: 0.45s; }
.overlay-title span:nth-child(5) { animation-delay: 0.6s; }
.overlay-title span:nth-child(6) { animation-delay: 0.75s; }
.overlay-title span:nth-child(7) { animation-delay: 0.9s; }
.overlay-title span:nth-child(8) { animation-delay: 1.05s; }

.tc-I { color: var(--color-piece-I); }
.tc-O { color: var(--color-piece-O); }
.tc-T { color: var(--color-piece-T); }
.tc-S { color: var(--color-piece-S); }
.tc-Z { color: var(--color-piece-Z); }
.tc-J { color: var(--color-piece-J); }
.tc-L { color: var(--color-piece-L); }

@keyframes title-glow {
  0%   { text-shadow: 0 0 8px currentColor, 0 0 20px currentColor; transform: translateY(0); }
  100% { text-shadow: 0 0 15px currentColor, 0 0 40px currentColor, 0 0 80px currentColor; transform: translateY(-2px); }
}

.overlay-heading {
  font-family: var(--font-heading);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-6);
  text-shadow: 0 0 15px rgba(224, 224, 255, 0.4), 0 0 30px rgba(224, 224, 255, 0.2);
}

.overlay-text {
  font-size: var(--font-size-base);
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}

.overlay-text kbd {
  color: var(--color-text-accent);
  border-color: var(--color-border-accent);
}

/* --- Mode Select --- */
.mode-select {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.mode-tabs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-2);
}

.mode-tab {
  font-family: var(--font-ui);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-muted);
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-3);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.mode-tab:hover {
  border-color: var(--color-border-accent);
  color: var(--color-text-primary);
}

.mode-tab.active {
  color: var(--color-bg-primary);
  background-color: var(--color-text-accent);
  border-color: var(--color-text-accent);
  box-shadow: 0 0 15px rgba(0, 212, 255, 0.4);
}

.mode-tab:focus-visible {
  outline: 2px solid var(--color-text-accent);
  outline-offset: 2px;
}

.start-menu-buttons {
  display: flex;
  gap: var(--space-2);
  margin-top: var(--space-2);
}

.start-menu-buttons .overlay-btn {
  font-size: var(--font-size-sm);
  padding: var(--space-2) var(--space-4);
  margin-bottom: 0;
}

#best-record {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}

#best-record .record-value {
  color: var(--color-text-accent);
  font-weight: var(--font-weight-bold);
}

#best-record.improved .record-value {
  color: #FFD700;
  text-shadow: 0 0 8px #FFD700;
}

/* --- Stats & Settings Overlay Layout --- */
#stats-overlay,
#settings-overlay {
  overflow-y: auto;
  padding: var(--space-4);
}

.stats-section,
.settings-section {
  width: 100%;
  max-width: 420px;
  margin-bottom: var(--space-4);
}

.stats-section-title {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-accent);
  text-transform: uppercase;
  letter-spacing: var(--letter-spacing-label);
  margin-bottom: var(--space-2);
  padding-bottom: var(--space-1);
  border-bottom: 1px solid var(--color-border);
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2) var(--space-4);
}

.stat-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: var(--font-size-sm);
  padding: 2px 0;
}

.stat-row .label {
  text-transform: none;
  letter-spacing: 0;
  font-weight: normal;
  font-size: var(--font-size-sm);
}

.stat-row .value {
  font-size: var(--font-size-sm);
}

.overlay-btn-row {
  display: flex;
  gap: var(--space-3);
  margin-top: var(--space-2);
}

/* --- Settings Specific --- */
.setting-row {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  padding: var(--space-2) 0;
}

.setting-row label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: var(--font-size-sm);
  color: var(--color-text-primary);
}

.vol-readout {
  font-family: var(--font-mono);
  color: var(--color-text-accent);
  font-size: var(--font-size-xs);
}

.setting-row input[type="range"] {
  width: 100%;
  cursor: pointer;
  accent-color: var(--color-text-accent);
}

.toggle-row {
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
}

.setting-row input[type="checkbox"] {
  width: 18px;
  height: 18px;
  cursor: pointer;
  accent-color: var(--color-text-accent);
}

#key-rebind-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.key-rebind {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-2) var(--space-3);
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: var(--font-size-sm);
  transition: border-color var(--transition-fast);
}

.key-rebind:hover {
  border-color: var(--color-border-accent);
}

.key-rebind.listening {
  border-color: var(--color-text-accent);
  background-color: rgba(0, 212, 255, 0.1);
}

.key-display {
  font-family: var(--font-mono);
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 2px var(--space-2);
  font-size: var(--font-size-xs);
  color: var(--color-text-accent);
  min-width: 60px;
  text-align: center;
}

/* --- Theme Tabs --- */
.theme-tabs {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.theme-tab {
  font-family: var(--font-ui);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-muted);
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-3);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-tab:hover {
  border-color: var(--color-border-accent);
  color: var(--color-text-primary);
}

.theme-tab.active {
  color: var(--color-bg-primary);
  background-color: var(--color-text-accent);
  border-color: var(--color-text-accent);
  box-shadow: 0 0 12px rgba(0, 212, 255, 0.3);
}

.theme-tab:focus-visible {
  outline: 2px solid var(--color-text-accent);
  outline-offset: 2px;
}

/* --- Tutorial --- */
.tutorial-page {
  display: none;
  flex-direction: column;
  align-items: center;
  gap: var(--space-3);
  max-width: 400px;
  width: 100%;
}

.tutorial-page.active {
  display: flex;
}

.tutorial-nav {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-top: var(--space-4);
}

.tutorial-dots {
  display: flex;
  gap: var(--space-2);
}

.tutorial-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-border);
  transition: background var(--transition-fast);
}

.tutorial-dot.active {
  background: var(--color-text-accent);
  box-shadow: 0 0 6px var(--color-text-accent);
}

.tutorial-controls {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  width: 100%;
}

.tutorial-type-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  width: 100%;
  padding: var(--space-2) 0;
}

.tutorial-piece-row {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  align-items: flex-start;
}

.tutorial-block {
  width: 14px;
  height: 14px;
  border-radius: 2px;
  display: inline-block;
}

.tutorial-block-br {
  width: 100%;
  height: 0;
  flex-basis: 100%;
}

.tutorial-spacer {
  width: 12px;
}

.tutorial-powers {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  width: 100%;
}

.tutorial-power-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--font-size-sm);
  color: var(--color-text-primary);
}

.tutorial-power-icon {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  flex-shrink: 0;
  box-shadow: 0 0 8px currentColor;
}

.tutorial-zone-flow {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  width: 100%;
}

.tutorial-zone-step {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--font-size-sm);
  color: var(--color-text-primary);
}

.tutorial-zone-num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-text-accent);
  color: var(--color-bg-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: var(--font-weight-bold);
  font-size: var(--font-size-sm);
  flex-shrink: 0;
}

/* --- Achievement Toast --- */
.achievement-toast {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--color-bg-surface);
  border: 1px solid #FFD700;
  border-radius: var(--radius-md);
  padding: 12px 16px;
  box-shadow: 0 0 20px rgba(255, 215, 0, 0.3);
  transform: translateX(calc(100% + 40px));
  transition: transform 400ms ease;
  pointer-events: none;
}

.achievement-toast.show {
  transform: translateX(0);
}

.achievement-icon {
  font-size: 24px;
}

.achievement-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.achievement-name {
  font-weight: var(--font-weight-bold);
  color: #FFD700;
  font-size: var(--font-size-sm);
}

.achievement-desc {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

/* --- Achievement Grid --- */
.achievements-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2);
}

.achievement-card {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2);
  background: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-xs);
}

.achievement-card.unlocked {
  border-left: 3px solid #FFD700;
}

.achievement-card.locked {
  opacity: 0.4;
  filter: grayscale(0.8);
}

.achievement-card-icon {
  font-size: 16px;
  flex-shrink: 0;
}

.achievement-card-info {
  display: flex;
  flex-direction: column;
}

.achievement-card-name {
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
}

.achievement-card-desc {
  color: var(--color-text-muted);
  font-size: 0.65rem;
}

/* --- Zone Meter --- */
.zone-meter {
  width: 100%;
  height: 8px;
  background: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  overflow: hidden;
}

.zone-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #33cc33, #66ff66);
  transition: width 200ms ease;
  border-radius: 3px;
}

.zone-status {
  font-size: var(--font-size-xs) !important;
  color: var(--color-text-accent);
}

/* --- Level Select --- */
.level-select {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.level-select-row {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.level-btn {
  font-size: var(--font-size-base);
  color: var(--color-text-primary);
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-3);
  cursor: pointer;
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
  line-height: 1;
}

.level-btn:hover {
  background-color: var(--color-border);
  border-color: var(--color-border-accent);
}

.level-btn:focus-visible {
  outline: 2px solid var(--color-text-accent);
  outline-offset: 2px;
}

#level-select-value {
  min-width: 2ch;
  text-align: center;
}

/* When mode select hides level container, keep spacing tight */
#level-select-container.hidden {
  display: none;
}

/* --- Overlay Action Buttons --- */
.overlay-btn {
  font-family: var(--font-ui);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-3) var(--space-6);
  cursor: pointer;
  margin-bottom: var(--space-3);
  box-shadow: var(--shadow-md);
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast),
              transform var(--transition-fast),
              box-shadow var(--transition-fast);
}

.overlay-btn:hover {
  background-color: var(--color-border);
  border-color: var(--color-border-accent);
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg), 0 0 20px rgba(0, 212, 255, 0.3);
}

.overlay-btn:active {
  background-color: var(--color-border-accent);
  transform: translateY(2px);
  box-shadow: var(--shadow-sm);
  filter: brightness(0.9);
}

.overlay-btn:focus-visible {
  outline: 2px solid var(--color-text-accent);
  outline-offset: 2px;
}

.overlay-btn--secondary {
  background-color: transparent;
  border-color: var(--color-border);
  box-shadow: none;
}

.overlay-btn--secondary:hover {
  background-color: var(--color-bg-surface);
  box-shadow: var(--shadow-md);
}

/* --- Game Over Stats --- */
.gameover-stats {
  display: flex;
  gap: var(--space-6);
  margin-bottom: var(--space-6);
}

.gameover-stats .stat-item {
  align-items: center;
}

#new-highscore-banner {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: #FFD700;
  text-shadow: 0 0 15px #FFD700, 0 0 30px #FFD700, 0 0 60px rgba(255, 215, 0, 0.5);
  margin-bottom: var(--space-4);
  letter-spacing: 0.1em;
  animation: title-glow 1.5s ease-in-out infinite alternate;
}

#gameover-detail-stats {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: var(--space-2);
  margin-bottom: var(--space-4);
  width: 100%;
  max-width: 400px;
}

.detail-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.detail-stat .label {
  font-size: 0.6rem;
}

.detail-stat .value {
  font-size: var(--font-size-sm);
}

@keyframes high-score-pulse {
  0%   { color: var(--color-text-accent); text-shadow: none; }
  50%  { color: #FFD700; text-shadow: 0 0 10px #FFD700; }
  100% { color: var(--color-text-accent); text-shadow: none; }
}

.high-score-glow {
  animation: high-score-pulse 1s ease-in-out 3;
}

/* --- Touch Controls --- */
#touch-controls {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-3) 0;
}

.touch-row {
  display: flex;
  justify-content: center;
  gap: var(--space-2);
}

#touch-controls button {
  min-width: var(--space-12);
  min-height: var(--space-12);
  font-size: var(--font-size-lg);
  background-color: var(--color-bg-surface);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  touch-action: manipulation;
  user-select: none;
  -webkit-user-select: none;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

#touch-controls button:hover {
  background-color: var(--color-border);
  border-color: var(--color-border-accent);
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg);
}

#touch-controls button:active {
  background-color: var(--color-border-accent);
}

/* --- General Hidden (non-overlay elements) --- */
.hidden:not(.overlay) {
  display: none !important;
}

/* ==========================================================================
   RESPONSIVE — Mobile (max-width: 700px)
   ========================================================================== */
@media (max-width: 780px) {
  #game-container {
    grid-template-columns: 1fr;
    max-width: min(384px, 92vw);
    padding: var(--space-3);
    gap: var(--space-3);
  }

  #stats-panel {
    flex-direction: row;
    justify-content: space-between;
    gap: var(--space-3);
    padding: var(--space-3);
  }

  #stats-panel .stat-item {
    align-items: center;
    flex: 1;
  }

  #stats-panel .value {
    font-size: var(--font-size-sm);
  }

  /* Hide time, high score, and PPS on mobile stats row to save space */
  #stats-panel .stat-item:nth-child(4),
  #stats-panel .stat-item:nth-child(5),
  #pps-display {
    display: none;
  }

  #right-panel {
    padding: var(--space-3);
  }

  #controls-panel {
    display: none;
  }

  .hold-piece-section,
  .next-piece-section {
    flex-direction: row;
    align-items: center;
    gap: var(--space-3);
  }

  #hold-canvas,
  #next-canvas {
    max-width: 80px;
  }

  .gameover-stats {
    flex-direction: column;
    gap: var(--space-3);
  }

  #gameover-detail-stats {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ==========================================================================
   REDUCED MOTION
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  .overlay {
    transition: none;
  }

  #score-value {
    transition: none;
  }

  .score-pop {
    transform: none;
  }

  body::before {
    animation: none;
  }
}