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

/* Light theme (default) */
:root,
[data-theme="light"] {
  --bg-deep: #eef2f8;
  --bg-mid: #e2e8f2;
  --bg-gradient-top: #dbeafe;
  --bg-panel: #ffffff;
  --bg-panel-solid: #ffffff;
  --border: rgba(15, 23, 42, 0.1);
  --border-strong: rgba(15, 23, 42, 0.16);
  --shadow: 0 4px 24px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 40px rgba(15, 23, 42, 0.1);
  --overlay: rgba(15, 23, 42, 0.45);
  --text: #0f172a;
  --text-dim: #475569;
  --text-muted: #64748b;
  --accent: #0891b2;
  --accent-strong: #0e7490;
  --accent-glow: rgba(8, 145, 178, 0.25);
  --accent-soft: rgba(8, 145, 178, 0.1);
  --accent-warm: #7c3aed;
  --accent-warm-soft: rgba(124, 58, 237, 0.12);
  --success: #059669;
  --success-glow: rgba(5, 150, 105, 0.2);
  --success-soft: rgba(5, 150, 105, 0.12);
  --error: #dc2626;
  --error-glow: rgba(220, 38, 38, 0.2);
  --error-soft: rgba(220, 38, 38, 0.1);
  --gold: #d97706;
  --top-bar-bg: rgba(255, 255, 255, 0.85);
  --piano-footer-bg: linear-gradient(0deg, rgba(226, 232, 240, 0.9) 0%, transparent 100%);
  --chip-bg: rgba(8, 145, 178, 0.1);
  --chip-border: rgba(8, 145, 178, 0.28);
  --surface-hover: rgba(8, 145, 178, 0.06);
  --card-hover-glow: rgba(8, 145, 178, 0.2);
  --btn-secondary-bg: #f1f5f9;
  --white-key: #fefefe;
  --white-key-active: #e2e8f0;
  --white-key-border: #cbd5e1;
  --black-key: #1e293b;
  --black-key-active: #334155;
  --piano-shadow: 0 -4px 20px rgba(15, 23, 42, 0.12);
  --bubble-text: #ffffff;
  --piano-height: clamp(100px, 18vh, 140px);
  --top-bar-height: 3.1rem;
  --floating-back-top: calc(var(--top-bar-height) + 0.35rem);
  --piano-offset: 0px;
}

[data-theme="dark"] {
  --bg-deep: #0a0e1a;
  --bg-mid: #121a2e;
  --bg-gradient-top: #1a2744;
  --bg-panel: rgba(255, 255, 255, 0.06);
  --bg-panel-solid: #151b2e;
  --border: rgba(255, 255, 255, 0.1);
  --border-strong: rgba(255, 255, 255, 0.16);
  --shadow: 0 8px 28px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.4);
  --overlay: rgba(10, 14, 26, 0.75);
  --text: #f1f5f9;
  --text-dim: #94a3b8;
  --text-muted: #64748b;
  --accent: #22d3ee;
  --accent-strong: #67e8f9;
  --accent-glow: rgba(34, 211, 238, 0.4);
  --accent-soft: rgba(34, 211, 238, 0.12);
  --accent-warm: #a78bfa;
  --accent-warm-soft: rgba(167, 139, 250, 0.15);
  --success: #34d399;
  --success-glow: rgba(52, 211, 153, 0.45);
  --success-soft: rgba(52, 211, 153, 0.15);
  --error: #f87171;
  --error-glow: rgba(248, 113, 113, 0.4);
  --error-soft: rgba(248, 113, 113, 0.12);
  --gold: #fbbf24;
  --top-bar-bg: linear-gradient(180deg, rgba(0, 0, 0, 0.35) 0%, transparent 100%);
  --piano-footer-bg: linear-gradient(0deg, rgba(0, 0, 0, 0.4) 0%, transparent 100%);
  --chip-bg: rgba(34, 211, 238, 0.12);
  --chip-border: rgba(34, 211, 238, 0.3);
  --surface-hover: rgba(34, 211, 238, 0.08);
  --card-hover-glow: rgba(34, 211, 238, 0.35);
  --btn-secondary-bg: rgba(255, 255, 255, 0.08);
  --white-key: #e8ecf4;
  --white-key-active: #c5d0e8;
  --white-key-border: #a8b4cc;
  --black-key: #1a2238;
  --black-key-active: #2d3a5c;
  --piano-shadow: 0 -4px 24px rgba(0, 0, 0, 0.4);
  --bubble-text: #0a0e1a;
  --piano-height: clamp(100px, 18vh, 140px);
}

html, body {
  height: 100%;
  height: 100dvh;
}

body {
  font-family: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  color: var(--text);
  background: radial-gradient(ellipse 120% 80% at 50% -20%, var(--bg-gradient-top) 0%, var(--bg-deep) 55%);
  min-height: 100dvh;
  max-height: 100dvh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  -webkit-font-smoothing: antialiased;
}

/* ── Top bar ── */
.top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  padding: 0.55rem 1rem;
  flex-shrink: 0;
  min-height: var(--top-bar-height);
  background: var(--top-bar-bg);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(8px);
}

.top-bar-left {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.app-title {
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text);
}

.app-title span {
  background: linear-gradient(135deg, var(--accent-strong), var(--accent-warm));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-panel);
  color: var(--text-dim);
  font-family: inherit;
  font-size: 0.72rem;
  font-weight: 700;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s, box-shadow 0.2s;
  box-shadow: var(--shadow);
}

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.theme-icon {
  font-size: 0.95rem;
  line-height: 1;
}

.piano-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-panel);
  color: var(--text-dim);
  font-family: inherit;
  font-size: 0.72rem;
  font-weight: 700;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s, box-shadow 0.2s, background 0.2s;
  box-shadow: var(--shadow);
}

.piano-toggle:hover {
  color: var(--text);
  border-color: var(--accent-warm);
}

.piano-toggle.active {
  color: var(--accent-strong);
  border-color: var(--accent);
  background: var(--accent-soft);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.piano-toggle-icon {
  font-size: 0.95rem;
  line-height: 1;
}

body:not(.piano-hidden) {
  --piano-offset: var(--piano-height);
}

body.piano-hidden .piano-area {
  display: none;
}

body.piano-hidden {
  --piano-offset: 0px;
}

@media (max-width: 520px) {
  .theme-label,
  .piano-toggle-label,
  .sound-toggle-label { display: none; }
  .theme-toggle,
  .piano-toggle,
  .sound-toggle { padding: 0.45rem 0.55rem; }
}

.top-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem 1.1rem;
  align-items: center;
}

.stat-pill {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  min-width: 3.5rem;
}

.stat-pill.wide {
  min-width: 5rem;
}

.stat-label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
}

.stat-value {
  font-size: 1.05rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--text);
}

.stat-value.accent {
  color: var(--accent-strong);
}

.streak-flame {
  display: inline-block;
  animation: flamePulse 1.2s ease-in-out infinite;
}

@keyframes flamePulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.15); }
}

/* ── Main layout ── */
.app-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  max-width: 900px;
  width: 100%;
  margin: 0 auto;
  padding: 0 0.65rem;
  min-height: 0;
  overflow: hidden;
}

.app-main:has(.screen-tool.active) {
  max-width: min(100%, 1180px);
  padding: 0 0.5rem;
}

.center-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 0.35rem 0 0.5rem;
  min-height: 0;
  overflow-y: auto;
}

.screen-menu.center-area {
  justify-content: flex-start;
  padding-top: 0.15rem;
  gap: 0.55rem;
}

/* ── Screens ── */
.screen {
  display: none;
  flex-direction: column;
  align-items: center;
  width: 100%;
  flex: 1;
  animation: fadeIn 0.35s ease;
}

.screen.active {
  display: flex;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Mode selection ── */
.mode-intro {
  text-align: center;
  margin-bottom: 1.25rem;
}

.mode-intro-compact {
  margin-bottom: 0.35rem;
}

.mode-intro-compact h2 {
  margin-bottom: 0.15rem;
}

.mode-intro h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
  color: var(--text);
}

.screen-menu .mode-intro-compact h2 {
  font-size: 1.35rem;
}

.mode-intro p {
  color: var(--text-dim);
  font-size: 0.9rem;
  max-width: 420px;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(155px, 1fr));
  gap: 0.85rem;
  width: 100%;
  max-width: 720px;
}

.mode-card {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.1rem 1rem;
  cursor: pointer;
  touch-action: manipulation;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
  text-align: left;
  position: relative;
  overflow: hidden;
  color: var(--text);
  box-shadow: var(--shadow);
}

.mode-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--accent-soft), transparent 60%);
  opacity: 0;
  transition: opacity 0.2s;
}

.mode-card:hover:not(.locked)::before {
  opacity: 1;
}

.mode-card:hover:not(.locked) {
  transform: translateY(-3px);
  border-color: var(--accent);
  box-shadow: var(--shadow-lg), 0 0 20px var(--card-hover-glow);
}

.mode-card.locked {
  opacity: 0.55;
  cursor: not-allowed;
}

.mode-card .mode-icon {
  font-size: 1.75rem;
  margin-bottom: 0.5rem;
}

.mode-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
  color: var(--text);
}

.mode-card p {
  font-size: 0.75rem;
  color: var(--text-dim);
  line-height: 1.35;
}

.mode-badge {
  display: inline-block;
  font-size: 0.6rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.2rem 0.45rem;
  border-radius: 4px;
  margin-top: 0.5rem;
}

.mode-badge.beginner { background: var(--success-soft); color: var(--success); }
.mode-badge.intermediate { background: var(--accent-warm-soft); color: var(--accent-warm); }
.mode-badge.advanced { background: rgba(217, 119, 6, 0.15); color: var(--gold); }
.mode-badge.completed { background: var(--success-soft); color: var(--success); }
.mode-badge.locked { background: var(--btn-secondary-bg); color: var(--text-muted); }

.back-btn {
  margin-top: 1.25rem;
  padding: 0.55rem 1.25rem;
  background: var(--bg-panel);
  border: 1px solid var(--border-strong);
  border-radius: 8px;
  color: var(--text-dim);
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
  box-shadow: var(--shadow);
}

.back-btn:hover {
  color: var(--text);
  border-color: var(--accent);
}

.back-btn-floating {
  position: fixed;
  top: var(--floating-back-top);
  left: 0.5rem;
  z-index: 200;
  margin: 0;
  padding: 0.4rem 0.75rem;
  font-size: 0.78rem;
  border-radius: 999px;
  backdrop-filter: blur(8px);
  background: var(--top-bar-bg);
}

#screen-game.active,
#screen-tutorial.active {
  flex: 1;
  min-height: 0;
  justify-content: flex-start;
  padding-top: 0.25rem;
  max-height: calc(100dvh - var(--top-bar-height) - var(--piano-offset) - 0.25rem);
  overflow-y: auto;
}

#screen-game .challenge-panel {
  margin-top: 0.15rem;
}

.screen-tool .tool-page-header-inset,
.screen-tutorial .tutorial-header {
  padding-left: 5.5rem;
}

@media (max-width: 768px) {
  :root,
  [data-theme="light"],
  [data-theme="dark"] {
    --top-bar-height: 5.75rem;
    --floating-back-top: 6.15rem;
  }
}

@media (max-width: 520px) {
  .back-btn-floating {
    padding: 0.35rem 0.55rem;
    font-size: 0.72rem;
  }
  .screen-tool .tool-page-header-inset,
  .screen-tutorial .tutorial-header {
    padding-left: 0.65rem;
    padding-top: 1.85rem;
  }
}

/* ── Game play ── */
.challenge-panel {
  width: 100%;
  max-width: 520px;
  text-align: center;
  padding: 1.5rem 1.25rem;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow-lg);
  transition: border-color 0.3s, box-shadow 0.3s;
  color: var(--text);
}

.challenge-panel.feedback-correct {
  border-color: var(--success);
  box-shadow: 0 0 32px var(--success-glow);
  animation: correctPulse 0.5s ease;
}

.challenge-panel.feedback-wrong {
  border-color: var(--error);
  box-shadow: 0 0 28px var(--error-glow);
  animation: wrongShake 0.45s ease;
}

@keyframes correctPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.02); }
}

@keyframes wrongShake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-8px); }
  40% { transform: translateX(8px); }
  60% { transform: translateX(-5px); }
  80% { transform: translateX(5px); }
}

.instruction {
  font-size: clamp(1.25rem, 4vw, 1.65rem);
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 0.65rem;
  color: var(--text);
}

.instruction .highlight {
  color: var(--accent-strong);
}

[data-theme="dark"] .instruction .highlight {
  text-shadow: 0 0 20px var(--accent-glow);
}

.sub-instruction {
  font-size: 0.9rem;
  color: var(--text-dim);
  min-height: 1.4em;
}

.score-line {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--text-dim);
  font-variant-numeric: tabular-nums;
}

.score-line strong {
  color: var(--accent-strong);
}

/* Memory sequence display */
.sequence-display {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  margin: 1rem 0 0.5rem;
  min-height: 2.5rem;
}

.sequence-chip {
  padding: 0.4rem 0.75rem;
  background: var(--chip-bg);
  border: 1px solid var(--chip-border);
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--accent-strong);
  animation: chipPop 0.3s ease;
}

@keyframes chipPop {
  from { transform: scale(0.6); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.chord-progress {
  display: flex;
  gap: 0.4rem;
  justify-content: center;
  margin-top: 0.75rem;
  min-height: 2rem;
}

.chord-slot {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 8px;
  border: 2px dashed var(--border-strong);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.chord-slot.filled {
  border-style: solid;
  border-color: var(--accent);
  color: var(--accent-strong);
  background: var(--chip-bg);
}

.submit-chord-btn {
  margin-top: 1rem;
  padding: 0.6rem 1.5rem;
  background: linear-gradient(135deg, #3b82f6, #6366f1);
  border: none;
  border-radius: 10px;
  color: white;
  font-weight: 700;
  font-size: 0.9rem;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}

.submit-chord-btn:hover {
  transform: scale(1.03);
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.45);
}

.submit-chord-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
}

/* ── XP popup ── */
.xp-popup-container {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 1000;
}

.xp-popup {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--success);
  text-shadow: 0 0 24px var(--success-glow);
  animation: xpFloat 1.1s ease forwards;
  white-space: nowrap;
}

.xp-popup.perfect {
  color: var(--gold);
  text-shadow: 0 0 24px rgba(217, 119, 6, 0.35);
  font-size: 2rem;
}

@keyframes xpFloat {
  0% { opacity: 0; transform: translateY(20px) scale(0.8); }
  15% { opacity: 1; transform: translateY(0) scale(1.1); }
  70% { opacity: 1; transform: translateY(-30px) scale(1); }
  100% { opacity: 0; transform: translateY(-60px) scale(0.9); }
}

.level-up-banner {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--overlay);
  z-index: 1100;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s;
}

.level-up-banner.visible {
  opacity: 1;
  pointer-events: auto;
}

.level-up-inner {
  text-align: center;
  animation: levelPop 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.level-up-inner h2 {
  font-size: 2.2rem;
  background: linear-gradient(135deg, var(--accent-strong), var(--accent-warm), #ec4899);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.level-up-inner p {
  color: var(--text-dim);
  margin-top: 0.35rem;
}

@keyframes levelPop {
  from { transform: scale(0.5); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

/* ── Piano ── */
.piano-area {
  padding: 0.75rem 1rem 1.25rem;
  background: var(--piano-footer-bg);
  border-top: 1px solid var(--border);
}

.piano-wrap {
  max-width: 640px;
  margin: 0 auto;
  position: relative;
}

.piano {
  display: flex;
  position: relative;
  height: var(--piano-height);
  border-radius: 0 0 10px 10px;
  overflow: visible;
  box-shadow: var(--piano-shadow), inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

.white-keys {
  display: flex;
  flex: 1;
  position: relative;
  z-index: 1;
}

.piano-key {
  flex: 1;
  position: relative;
  border: none;
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: background 0.08s, transform 0.08s;
}

.piano-key.white {
  background: linear-gradient(180deg, var(--white-key) 0%, var(--white-key-active) 100%);
  border-right: 1px solid var(--white-key-border);
  border-radius: 0 0 6px 6px;
  z-index: 1;
}

.piano-key.white:first-child {
  border-radius: 0 0 0 8px;
}

.piano-key.white:last-child {
  border-right: none;
  border-radius: 0 0 8px 0;
}

.piano-key.white.pressed,
.piano-key.white:active {
  background: var(--white-key-active);
  transform: translateY(2px);
}

.piano-key.black {
  position: absolute;
  width: 9%;
  height: 62%;
  top: 0;
  z-index: 2;
  background: linear-gradient(180deg, #3d4d6e 0%, var(--black-key) 40%, #0d1220 100%);
  border-radius: 0 0 5px 5px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.5);
}

.piano-key.black.pressed,
.piano-key.black:active {
  background: linear-gradient(180deg, #4d5f85 0%, var(--black-key-active) 100%);
  transform: translateY(2px);
}

.piano-key.flash-demo {
  animation: keyFlash 0.45s ease;
}

.piano-key.flash-correct {
  animation: keyCorrect 0.6s ease;
}

.piano-key.flash-wrong {
  animation: keyWrong 0.5s ease;
}

@keyframes keyFlash {
  0%, 100% { box-shadow: none; }
  30% { box-shadow: 0 0 20px var(--accent-glow), inset 0 0 12px var(--accent); }
}

@keyframes keyCorrect {
  0%, 100% { box-shadow: none; }
  40% { box-shadow: 0 0 24px var(--success-glow); }
}

@keyframes keyWrong {
  0%, 100% { }
  40% { box-shadow: 0 0 20px var(--error-glow); }
}

.key-label {
  position: absolute;
  bottom: 8%;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.65rem;
  font-weight: 600;
  color: rgba(30, 40, 60, 0.5);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s;
}

.piano-key.white .key-label {
  color: rgba(30, 40, 60, 0.55);
}

.piano-key.show-label .key-label {
  opacity: 1;
}

.note-bubble {
  position: absolute;
  top: -28px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent-strong);
  color: var(--bubble-text);
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  pointer-events: none;
  animation: bubbleUp 0.7s ease forwards;
  z-index: 10;
  white-space: nowrap;
}

@keyframes bubbleUp {
  0% { opacity: 0; transform: translateX(-50%) translateY(8px); }
  20% { opacity: 1; transform: translateX(-50%) translateY(0); }
  80% { opacity: 1; }
  100% { opacity: 0; transform: translateX(-50%) translateY(-12px); }
}

.piano.disabled .piano-key {
  pointer-events: none;
  opacity: 0.85;
}

/* Black key positions (% from left of piano) */
.piano-key.black[data-note="Cs"] { left: 11%; }
.piano-key.black[data-note="Ds"] { left: 25%; }
.piano-key.black[data-note="Fs"] { left: 53%; }
.piano-key.black[data-note="Gs"] { left: 67%; }
.piano-key.black[data-note="As"] { left: 81%; }

/* Mobile: explicit sound unlock (iOS requires gesture + sync Web Audio) */
.audio-unlock-wrap {
  position: fixed;
  left: 50%;
  bottom: calc(var(--piano-offset, 0px) + 1rem);
  transform: translateX(-50%);
  z-index: 2000;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  max-width: calc(100vw - 2rem);
}

.audio-unlock-wrap.audio-unlock-hide {
  opacity: 0;
  transform: translateX(-50%) translateY(12px);
  transition: opacity 0.3s, transform 0.3s;
  pointer-events: none;
}

.audio-unlock-help {
  border: none;
  background: var(--bg-panel);
  color: var(--accent-strong);
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.5rem 0.85rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

.audio-unlock-banner {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 1.25rem;
  border: none;
  border-radius: 999px;
  background: var(--accent-strong);
  color: var(--bubble-text, #fff);
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 700;
  box-shadow: 0 8px 28px var(--accent-glow), 0 2px 8px rgba(0, 0, 0, 0.2);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  animation: audioUnlockPulse 2s ease-in-out infinite;
  max-width: calc(100vw - 2rem);
}

.audio-unlock-icon {
  font-size: 1.2rem;
  line-height: 1;
}

@keyframes audioUnlockPulse {
  0%, 100% { box-shadow: 0 8px 28px var(--accent-glow), 0 2px 8px rgba(0, 0, 0, 0.2); }
  50% { box-shadow: 0 10px 36px var(--accent-glow), 0 4px 12px rgba(0, 0, 0, 0.25); }
}

@media (max-width: 480px) {
  .top-bar { padding: 0.65rem 0.85rem; }
  .stat-pill { min-width: 2.8rem; }
  .stat-value { font-size: 0.9rem; }
  .mode-grid { grid-template-columns: 1fr; }
  .key-label { font-size: 0.55rem; }
}