/* ==========================================================================
   CleanTune — Design System
   Apple-inspired: light-first, soft neutrals, generous space, precise motion.
   ========================================================================== */

:root {
  /* Color — light (default) */
  --bg: #f5f5f7;
  --bg-elevated: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f0f2;
  --border: rgba(0, 0, 0, 0.08);
  --border-strong: rgba(0, 0, 0, 0.14);
  --text-primary: #1d1d1f;
  --text-secondary: #48484a;
  --text-tertiary: #86868b;

  --accent: #0a84ff;
  --accent-hover: #3396ff;
  --accent-soft: rgba(10, 132, 255, 0.14);

  --in-tune: #30d158;
  --in-tune-soft: rgba(48, 209, 88, 0.14);
  --flat: #ff9f0a;
  --sharp: #ff453a;
  --gradient-brand: linear-gradient(135deg, #0a84ff 0%, #bf5af2 100%);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 999px;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.12);

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --dur-fast: 150ms;
  --dur-base: 300ms;
  --dur-slow: 550ms;

  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI",
    Roboto, Helvetica, Arial, sans-serif;

  --container: 1120px;
  --header-h: 64px;
}

:root[data-theme="dark"] {
  --bg: #000000;
  --bg-elevated: #111113;
  --bg-card: #18181b;
  --bg-card-hover: #202024;
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);
  --text-primary: #f5f5f7;
  --text-secondary: #a1a1a6;
  --text-tertiary: #6e6e73;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.45);
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  min-height: 100dvh;
  transition: background var(--dur-base) var(--ease), color var(--dur-base) var(--ease);
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
  cursor: pointer;
}

input {
  font: inherit;
  color: inherit;
}

ul {
  list-style: none;
}

h1, h2, h3, h4 {
  font-weight: 600;
  letter-spacing: -0.02em;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* ---------- Layout ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 24px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  background: color-mix(in srgb, var(--bg) 72%, transparent);
  border-bottom: 1px solid var(--border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.brand-mark {
  width: 26px;
  height: 26px;
  flex-shrink: 0;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.main-nav a {
  display: block;
  padding: 8px 14px;
  border-radius: var(--radius-full);
  font-size: 14px;
  color: var(--text-secondary);
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
  background: var(--bg-card);
  color: var(--text-primary);
}

.nav-toggle {
  display: none;
}

.theme-toggle {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  transition: background var(--dur-fast) var(--ease);
}

.theme-toggle:hover {
  background: var(--bg-card);
}

@media (max-width: 760px) {
  .main-nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border);
    padding: 8px 16px 16px;
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--dur-base) var(--ease), opacity var(--dur-base) var(--ease);
  }

  .main-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .main-nav a {
    padding: 12px 10px;
  }

  .nav-toggle {
    display: grid;
    place-items: center;
    width: 36px;
    height: 36px;
  }

}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--radius-full);
  font-size: 15px;
  font-weight: 600;
  transition: transform var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
  white-space: nowrap;
}

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

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 6px 20px rgba(10, 132, 255, 0.35);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-strong);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
}

.btn-ghost {
  color: var(--text-secondary);
}

.btn-ghost:hover {
  color: var(--text-primary);
}

.btn-lg {
  padding: 16px 30px;
  font-size: 17px;
}

.btn-block {
  width: 100%;
}

/* ---------- Cards ---------- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

/* ---------- Hero ---------- */
.hero {
  padding: 72px 0 48px;
  text-align: center;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  margin-bottom: 20px;
  letter-spacing: 0.01em;
}

.hero h1 {
  font-size: clamp(36px, 6vw, 64px);
  line-height: 1.05;
  margin-bottom: 16px;
}

.hero h1 .grad {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero p {
  font-size: clamp(16px, 2vw, 19px);
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

/* Instrument selector */
.instrument-picker {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin: 40px auto 0;
  flex-wrap: wrap;
}

.instrument-chip {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  width: 128px;
  padding: 20px 12px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border);
  transition: transform var(--dur-base) var(--ease-spring), border-color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}

.instrument-chip:hover {
  transform: translateY(-4px);
  border-color: var(--border-strong);
}

.instrument-chip.active {
  border-color: transparent;
  background: var(--accent-soft);
  transform: translateY(-6px);
  box-shadow: 0 12px 28px rgba(10, 132, 255, 0.28), 0 0 0 1.5px var(--accent);
}

.instrument-chip .icon {
  width: 23px;
  height: 38px;
  color: var(--text-primary);
  transition: transform var(--dur-base) var(--ease-spring);
}

.instrument-chip.active .icon {
  transform: scale(1.08);
  color: var(--accent);
}

.instrument-chip span {
  font-size: 14px;
  font-weight: 600;
}

@media (max-width: 600px) {
  .instrument-picker {
    flex-wrap: nowrap;
    justify-content: flex-start;
    overflow-x: auto;
    overflow-y: visible;
    scroll-snap-type: x proximity;
    padding: 16px 20px 12px;
    margin-inline: -20px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

  .instrument-chip.active {
    transform: translateY(-4px);
    box-shadow: 0 6px 14px rgba(10, 132, 255, 0.26), 0 0 0 1.5px var(--accent);
  }

  .instrument-picker::-webkit-scrollbar {
    display: none;
  }

  .instrument-chip {
    width: 92px;
    padding: 14px 8px;
    flex-shrink: 0;
    scroll-snap-align: center;
  }

  .instrument-chip .icon {
    width: 18px;
    height: 30px;
  }

  .instrument-chip span {
    font-size: 12.5px;
  }
}

/* ---------- Section ---------- */
.section {
  padding: 64px 0;
}

.section-head {
  max-width: 640px;
  margin: 0 auto 40px;
  text-align: center;
}

.section-head h2 {
  font-size: clamp(26px, 4vw, 36px);
  margin-bottom: 12px;
}

.section-head p {
  color: var(--text-secondary);
  font-size: 17px;
}

/* ---------- Tuner ---------- */
.tuner-panel {
  position: relative;
  max-width: 560px;
  margin: 0 auto;
  padding: 40px 32px 32px;
  text-align: center;
}

.tuner-panel::before {
  content: "";
  position: absolute;
  top: -70px;
  left: 50%;
  transform: translateX(-50%);
  width: 60%;
  height: 130px;
  background: var(--gradient-brand);
  filter: blur(56px);
  opacity: 0.24;
  z-index: -1;
  pointer-events: none;
  border-radius: 50%;
}

:root[data-theme="dark"] .tuner-panel::before {
  opacity: 0.3;
}

.tuner-note-display {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 32px 0 24px;
}

.tuner-note {
  font-size: 96px;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1;
  transition: color var(--dur-base) var(--ease);
  color: var(--text-primary);
}

.tuner-note.in-tune { color: var(--in-tune); }
.tuner-note.flat { color: var(--flat); }
.tuner-note.sharp { color: var(--sharp); }

.tuner-freq {
  margin-top: 8px;
  font-size: 15px;
  color: var(--text-tertiary);
  font-variant-numeric: tabular-nums;
}

.tuner-meter {
  position: relative;
  width: 100%;
  max-width: 420px;
  height: 64px;
  margin: 8px auto 0;
}

.tuner-meter-track {
  position: absolute;
  left: 0;
  right: 0;
  top: 28px;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--bg-elevated);
  overflow: hidden;
  border: 1px solid var(--border);
}

.tuner-meter-track::before {
  content: "";
  position: absolute;
  inset: 0;
  left: 50%;
  width: 1px;
  background: var(--border-strong);
}

.tuner-meter-fill {
  position: absolute;
  top: 0;
  left: 50%;
  height: 100%;
  width: 0%;
  background: var(--text-tertiary);
  transform-origin: left center;
  transition: width var(--dur-fast) linear, background var(--dur-fast) var(--ease);
  border-radius: var(--radius-full);
}

.tuner-meter-fill.in-tune { background: var(--in-tune); }
.tuner-meter-fill.flat { background: var(--flat); }
.tuner-meter-fill.sharp { background: var(--sharp); }

.tuner-needle {
  position: absolute;
  top: 12px;
  left: 50%;
  width: 3px;
  height: 34px;
  border-radius: var(--radius-full);
  background: var(--text-primary);
  transform: translateX(-50%) rotate(0deg);
  transform-origin: bottom center;
  transition: transform 120ms var(--ease);
  box-shadow: 0 0 12px rgba(255, 255, 255, 0.25);
}

.tuner-meter-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 8px;
  font-size: 12px;
  color: var(--text-tertiary);
  font-weight: 600;
}

.tuner-mic-btn {
  width: 84px;
  height: 84px;
  border-radius: 50%;
  background: var(--gradient-brand);
  color: #fff;
  display: grid;
  place-items: center;
  margin: 28px auto 0;
  box-shadow: var(--shadow-md);
  transition: transform var(--dur-fast) var(--ease-spring);
}

.tuner-mic-btn:hover { transform: scale(1.05); }
.tuner-mic-btn:active { transform: scale(0.94); }

.tuner-mic-btn.listening {
  animation: pulse-ring 1.6s var(--ease) infinite;
}

@keyframes pulse-ring {
  0% { box-shadow: 0 0 0 0 rgba(10, 132, 255, 0.4), var(--shadow-md); }
  70% { box-shadow: 0 0 0 18px rgba(10, 132, 255, 0), var(--shadow-md); }
  100% { box-shadow: 0 0 0 0 rgba(10, 132, 255, 0), var(--shadow-md); }
}

.tuner-mic-btn svg { width: 32px; height: 32px; }

.tuner-status {
  margin-top: 16px;
  font-size: 14px;
  color: var(--text-tertiary);
  min-height: 20px;
}

/* String presets */
.string-select {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin-top: 28px;
}

.string-btn {
  position: relative;
  padding: 10px 16px;
  border-radius: var(--radius-full);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  font-size: 14px;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  transition: all var(--dur-fast) var(--ease);
}

.string-btn:hover { border-color: var(--border-strong); }

.string-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  padding-right: 26px;
}

.string-btn.active::after {
  content: "×";
  position: absolute;
  right: 8px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 13px;
  font-weight: 700;
  opacity: 0.8;
}

.tuning-select-wrap {
  margin-top: 20px;
}

.tuning-select {
  padding: 8px 14px;
  border-radius: var(--radius-full);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  font-size: 13px;
  color: var(--text-secondary);
}

/* ---------- Metronome ---------- */
.metronome-panel {
  max-width: 480px;
  margin: 0 auto;
  padding: 40px 32px;
  text-align: center;
}

.metronome-bpm {
  font-size: 88px;
  font-weight: 700;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
}

.metronome-bpm-label {
  color: var(--text-tertiary);
  font-size: 14px;
  margin-top: -8px;
  margin-bottom: 24px;
}

.metronome-slider-row {
  display: flex;
  align-items: center;
  gap: 16px;
}

.bpm-step-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  font-size: 20px;
  font-weight: 700;
  flex-shrink: 0;
  transition: background var(--dur-fast) var(--ease);
}

.bpm-step-btn:hover { background: var(--bg-card-hover); }

input[type="range"].bpm-slider {
  -webkit-appearance: none;
  appearance: none;
  flex: 1;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
}

input[type="range"].bpm-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: #fff;
  border: 3px solid var(--accent);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
}

input[type="range"].bpm-slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: #fff;
  border: 3px solid var(--accent);
  cursor: pointer;
}

.beat-dots {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin: 32px 0;
}

.beat-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  transition: background var(--dur-fast) var(--ease), transform 100ms var(--ease-spring);
}

.beat-dot.on {
  background: var(--accent);
  transform: scale(1.35);
}

.beat-dot.accent.on {
  background: var(--sharp);
}

.metronome-controls {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-top: 8px;
  flex-wrap: wrap;
}

.play-btn {
  width: 84px;
  height: 84px;
  border-radius: 50%;
  background: var(--gradient-brand);
  color: #fff;
  display: grid;
  place-items: center;
  box-shadow: var(--shadow-md);
  transition: transform var(--dur-fast) var(--ease-spring);
}

.play-btn:hover { transform: scale(1.05); }
.play-btn svg { width: 30px; height: 30px; }

/* ---------- Ear training ---------- */
.game-panel {
  max-width: 560px;
  margin: 0 auto;
  padding: 40px 32px;
}

.game-progress {
  display: flex;
  gap: 6px;
  margin-bottom: 28px;
}

.game-progress-seg {
  flex: 1;
  height: 4px;
  border-radius: var(--radius-full);
  background: var(--bg-elevated);
  overflow: hidden;
}

.game-progress-seg::after {
  content: "";
  display: block;
  height: 100%;
  width: 0%;
  background: var(--accent);
  transition: width var(--dur-base) var(--ease);
}

.game-progress-seg.done::after { width: 100%; }
.game-progress-seg.correct::after { background: var(--in-tune); }
.game-progress-seg.wrong::after { background: var(--sharp); }

.game-level-badge {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 6px 12px;
  border-radius: var(--radius-full);
  margin-bottom: 16px;
}

.game-prompt {
  text-align: center;
  margin: 24px 0 32px;
}

.game-prompt h2 {
  font-size: 24px;
  margin-bottom: 8px;
}

.game-prompt p {
  color: var(--text-secondary);
  font-size: 15px;
}

.replay-btn {
  width: 96px;
  height: 96px;
  border-radius: 50%;
  background: var(--gradient-brand);
  color: #fff;
  display: grid;
  place-items: center;
  margin: 0 auto 32px;
  box-shadow: var(--shadow-md);
  transition: transform var(--dur-fast) var(--ease-spring);
}

.replay-btn:hover { transform: scale(1.05) rotate(-4deg); }
.replay-btn svg { width: 34px; height: 34px; }

.game-options {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}

.game-option {
  padding: 16px 12px;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  font-size: 15px;
  font-weight: 600;
  transition: all var(--dur-fast) var(--ease);
}

.game-option:hover {
  border-color: var(--border-strong);
  background: var(--bg-card-hover);
}

.game-option.correct {
  background: var(--in-tune-soft);
  border-color: var(--in-tune);
  color: var(--in-tune);
}

.game-option.wrong {
  background: rgba(255, 69, 58, 0.14);
  border-color: var(--sharp);
  color: var(--sharp);
}

.game-option:disabled {
  pointer-events: none;
  opacity: 0.6;
}

.game-option:disabled.correct,
.game-option:disabled.wrong {
  opacity: 1;
}

/* Results */
.result-panel {
  max-width: 480px;
  margin: 0 auto;
  padding: 48px 32px;
  text-align: center;
}

.result-score {
  font-size: 88px;
  font-weight: 800;
  letter-spacing: -0.03em;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  line-height: 1;
}

.result-title {
  font-size: 20px;
  font-weight: 700;
  margin: 8px 0 4px;
}

.result-sub {
  color: var(--text-secondary);
  font-size: 15px;
  margin-bottom: 28px;
}

.name-input {
  width: 100%;
  padding: 14px 18px;
  border-radius: var(--radius-full);
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  text-align: center;
  font-size: 15px;
  margin-bottom: 16px;
}

.name-input:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.share-card-preview {
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 20px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
}

.share-card-preview canvas {
  width: 100%;
  height: auto;
  display: block;
}

.result-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* ---------- Content sections (SEO copy) ---------- */
.prose {
  max-width: 720px;
  margin: 0 auto;
}

.prose h2 {
  font-size: 26px;
  margin: 40px 0 14px;
}

.prose h2:first-child { margin-top: 0; }

.prose p {
  color: var(--text-secondary);
  font-size: 16px;
  margin-bottom: 14px;
}

.prose ul {
  margin: 0 0 14px 0;
}

.prose li {
  color: var(--text-secondary);
  font-size: 16px;
  padding-left: 22px;
  position: relative;
  margin-bottom: 8px;
}

.prose li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}

.tip-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin: 24px 0 40px;
}

.tip-card {
  padding: 22px;
  border-radius: var(--radius-md);
}

.tip-card .icon {
  width: 28px;
  height: 28px;
  color: var(--accent);
  margin-bottom: 12px;
}

.tip-card h3 {
  font-size: 15px;
  margin-bottom: 6px;
}

.tip-card p {
  font-size: 14px;
  color: var(--text-secondary);
}

/* FAQ */
.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 18px 0;
}

.faq-item summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 16px;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary .chev {
  width: 18px;
  height: 18px;
  color: var(--text-tertiary);
  transition: transform var(--dur-fast) var(--ease);
  flex-shrink: 0;
}

.faq-item[open] summary .chev { transform: rotate(180deg); }

.faq-item p {
  color: var(--text-secondary);
  font-size: 15px;
  margin-top: 12px;
  line-height: 1.6;
}

/* ---------- Tool cross-links ---------- */
.tool-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.tool-link-card {
  padding: 24px;
  border-radius: var(--radius-md);
  transition: transform var(--dur-base) var(--ease), border-color var(--dur-fast) var(--ease);
}

.tool-link-card:hover {
  transform: translateY(-3px);
  border-color: var(--border-strong);
}

.tool-link-card .icon {
  width: 26px;
  height: 26px;
  color: var(--accent);
  margin-bottom: 14px;
}

.tool-link-card h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

.tool-link-card p {
  font-size: 14px;
  color: var(--text-secondary);
}

/* ---------- Ad slots ---------- */
.ad-slot {
  max-width: var(--container);
  margin: 32px auto;
  padding-inline: 24px;
  display: flex;
  justify-content: center;
}

.ad-slot-inner {
  width: 100%;
  min-height: 90px;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px dashed var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  font-size: 12px;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 40px 0;
  margin-top: 64px;
}

.footer-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 24px;
}

.footer-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-links a {
  font-size: 14px;
  color: var(--text-secondary);
  transition: color var(--dur-fast) var(--ease);
}

.footer-links a:hover { color: var(--text-primary); }

.footer-copy {
  font-size: 13px;
  color: var(--text-tertiary);
}

/* ---------- Install banner ---------- */
.install-banner {
  position: fixed;
  left: 16px;
  right: 16px;
  bottom: 16px;
  max-width: 420px;
  margin: 0 auto;
  z-index: 200;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow-lg);
  transform: translateY(120%);
  opacity: 0;
  transition: transform var(--dur-slow) var(--ease-spring), opacity var(--dur-base) var(--ease);
}

.install-banner.visible {
  transform: translateY(0);
  opacity: 1;
}

.install-banner .icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.install-banner-text {
  flex: 1;
  min-width: 0;
}

.install-banner-text strong {
  display: block;
  font-size: 14px;
}

.install-banner-text span {
  font-size: 12px;
  color: var(--text-secondary);
}

.install-banner-close {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  color: var(--text-tertiary);
  flex-shrink: 0;
}

/* ---------- Utility animations ---------- */
.fade-in-up {
  animation: fadeInUp var(--dur-slow) var(--ease) both;
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

.pop-in {
  animation: popIn var(--dur-base) var(--ease-spring) both;
}

@keyframes popIn {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}

@media (max-width: 600px) {
  .hero { padding: 20px 0 12px; }
  .hero-eyebrow { margin-bottom: 10px; font-size: 12px; padding: 5px 12px; }
  .hero h1 { font-size: clamp(28px, 8vw, 40px); margin-bottom: 8px; }
  .hero p { font-size: 14px; margin-bottom: 0; }
  .instrument-picker { margin-top: 18px; }
  .tuner-panel { padding: 20px 24px 24px; }
  .tuner-note-display { padding: 16px 0 12px; }
  .tuner-note { font-size: 56px; }
  .tuner-mic-btn { width: 68px; height: 68px; margin-top: 16px; }
  .metronome-bpm { font-size: 64px; }
  .game-options { grid-template-columns: 1fr; }
}

/* ---------- Feedback / suggestion box ---------- */
.feedback-fab {
  position: fixed;
  right: 20px;
  bottom: 90px;
  z-index: 150;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  color: var(--text-primary);
  display: grid;
  place-items: center;
  box-shadow: var(--shadow-md);
  transition: transform var(--dur-fast) var(--ease-spring), background var(--dur-fast) var(--ease);
}

.feedback-fab:hover {
  transform: translateY(-3px) scale(1.05);
  background: var(--bg-card-hover);
}

.feedback-fab svg {
  width: 20px;
  height: 20px;
}

.feedback-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: 300;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur-base) var(--ease);
}

.feedback-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.feedback-modal {
  width: 100%;
  max-width: 420px;
  padding: 28px 26px;
  position: relative;
  transform: translateY(12px) scale(0.97);
  transition: transform var(--dur-base) var(--ease-spring);
}

.feedback-overlay.open .feedback-modal {
  transform: translateY(0) scale(1);
}

.feedback-modal-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: var(--text-tertiary);
  transition: background var(--dur-fast) var(--ease);
}

.feedback-modal-close:hover {
  background: var(--bg-elevated);
}

.feedback-modal h2 {
  font-size: 20px;
  margin-bottom: 6px;
}

.feedback-modal p {
  color: var(--text-secondary);
  font-size: 14px;
  margin-bottom: 20px;
}

.feedback-field {
  margin-bottom: 14px;
  text-align: left;
}

.feedback-field label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-secondary);
}

.feedback-field select,
.feedback-field input,
.feedback-field textarea {
  width: 100%;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  font-size: 14px;
  font-family: inherit;
  color: var(--text-primary);
}

.feedback-field select:focus,
.feedback-field input:focus,
.feedback-field textarea:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

.feedback-field textarea {
  resize: vertical;
  min-height: 90px;
}

.feedback-status {
  font-size: 13px;
  margin-top: 10px;
  min-height: 18px;
  color: var(--text-tertiary);
}

.feedback-status.error {
  color: var(--sharp);
}

.feedback-success {
  text-align: center;
  padding: 12px 0 4px;
}

.feedback-success svg {
  width: 40px;
  height: 40px;
  color: var(--in-tune);
  margin: 0 auto 12px;
}

.feedback-success h2 {
  margin-bottom: 6px;
}

@media (max-width: 600px) {
  .feedback-fab {
    right: 16px;
    bottom: 84px;
    width: 44px;
    height: 44px;
  }
}

/* ---------- Tuned celebration toast ---------- */
.tuned-toast {
  position: fixed;
  left: 16px;
  right: 16px;
  bottom: 90px;
  max-width: 420px;
  margin: 0 auto;
  z-index: 200;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 18px;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px solid var(--in-tune);
  box-shadow: var(--shadow-lg);
  transform: translateY(120%);
  opacity: 0;
  pointer-events: none;
  transition: transform var(--dur-slow) var(--ease-spring), opacity var(--dur-base) var(--ease);
}

.tuned-toast.visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.tuned-toast-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--in-tune-soft);
  color: var(--in-tune);
  display: grid;
  place-items: center;
  flex-shrink: 0;
}

.tuned-toast-icon svg {
  width: 22px;
  height: 22px;
}

.tuned-toast-text {
  flex: 1;
  min-width: 0;
}

.tuned-toast-text strong {
  display: block;
  font-size: 14px;
}

.tuned-toast-text span {
  font-size: 12px;
  color: var(--text-secondary);
}

.tuned-toast-close {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  color: var(--text-tertiary);
  flex-shrink: 0;
}