:root {
  --bg: #080b12;
  --surface: #0f1520;
  --border: #1a2535;
  --accent: #00e5ff;
  --accent-dim: rgba(0, 229, 255, 0.12);
  --accent-glow: rgba(0, 229, 255, 0.35);
  --text: #c8d8e8;
  --muted: #4a6075;
  --radius: 8px;
}

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

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: 14px;
}

body {
  display: flex;
  align-items: safe center;
  justify-content: center;
  min-height: 100dvh;
  padding: 12px 16px;
}

.app {
  width: 100%;
  max-width: 640px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

/* ── Header ── */

.app-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
  flex-wrap: wrap;
}

.app-title {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  align-self: center;
}

.randomize-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 7px 16px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  display: flex;
  align-items: center;
  gap: 7px;
  transition: border-color 0.18s, color 0.18s, box-shadow 0.18s;
  white-space: nowrap;
}

.randomize-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}

.randomize-icon { display: inline-block; font-size: 15px; line-height: 1; }

@keyframes spin-once {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}

.randomize-icon.spin { animation: spin-once 0.45s cubic-bezier(0.4, 0, 0.2, 1); }

/* ── Visualizer ── */

.visualizer-container {
  width: 100%;
  height: 160px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  position: relative;
}

#visualizer { width: 100%; height: 100%; display: block; }

/* ── Controls panel ── */

.controls {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 22px;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.controls-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 2px 0;
}

.controls-divider {
  border-top: 1px solid var(--border);
  margin: 10px 0;
}

.group-title {
  color: var(--muted);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 2px;
}

.slider-row {
  display: grid;
  grid-template-columns: 74px 1fr 68px;
  align-items: center;
  gap: 12px;
}

.slider-label {
  color: var(--muted);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  cursor: default;
}

.slider-value {
  color: var(--muted);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  text-align: right;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  outline: none;
  cursor: pointer;
  background: var(--border);
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  box-shadow: 0 0 8px var(--accent-glow);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.25);
  box-shadow: 0 0 16px var(--accent-glow);
}

input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
  box-shadow: 0 0 8px var(--accent-glow);
}

input[type="range"]::-moz-range-track {
  height: 4px;
  border-radius: 2px;
  background: var(--border);
}

/* ── Octave toggle ── */

.toggle-group {
  display: flex;
  gap: 6px;
}

.toggle-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 4px 14px;
  border-radius: 20px;
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  transition: border-color 0.15s, color 0.15s, background 0.15s, box-shadow 0.15s;
  line-height: 1.4;
}

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

.toggle-btn.active {
  background: var(--accent-dim);
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}

/* ── Presets ── */

.presets-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.preset-groups {
  flex-wrap: wrap;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.preset-grid {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.preset-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 5px 14px;
  border-radius: 20px;
  cursor: pointer;
  font-size: 12px;
  font-family: inherit;
  transition: border-color 0.15s, color 0.15s, background 0.15s, box-shadow 0.15s;
  white-space: nowrap;
}

.preset-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}

.preset-btn.active {
  background: var(--accent-dim);
  border-color: var(--accent);
  color: var(--accent);
}

/* ── Footer ── */

.app-footer {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.play-btn {
  flex: 1;
  min-width: 100px;
  height: 52px;
  background: transparent;
  border: 2px solid var(--border);
  color: var(--text);
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 15px;
  font-family: inherit;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: border-color 0.18s, color 0.18s, box-shadow 0.18s, background 0.18s;
}

.play-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 18px var(--accent-glow);
}

.play-btn.active {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
  box-shadow: 0 0 22px var(--accent-glow);
}

.play-btn.loading { opacity: 0.5; pointer-events: none; }

.play-icon { font-size: 16px; line-height: 1; }

.export-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 11px 20px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  transition: border-color 0.18s, color 0.18s, box-shadow 0.18s;
  white-space: nowrap;
}

.export-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}

.export-btn:disabled { opacity: 0.45; cursor: not-allowed; pointer-events: none; }

/* ── Record button ── */

.record-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 11px 20px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  transition: border-color 0.18s, color 0.18s, box-shadow 0.18s;
  white-space: nowrap;
}

.record-btn:hover {
  border-color: #ff4444;
  color: #ff4444;
  box-shadow: 0 0 10px rgba(255, 68, 68, 0.35);
}

.record-btn.recording {
  border-color: #ff4444;
  color: #ff4444;
  background: rgba(255, 68, 68, 0.1);
  animation: pulse-record 1s ease-in-out infinite;
}

@keyframes pulse-record {
  0%, 100% { box-shadow: 0 0 8px rgba(255, 68, 68, 0.3); }
  50%       { box-shadow: 0 0 20px rgba(255, 68, 68, 0.6); }
}

/* ── Contextual controls ── */

[hidden] { display: none !important; }

.app[data-kind="noise"] [data-show="drone"] { display: none; }

.mod-group summary {
  cursor: pointer;
  list-style: none;
  user-select: none;
}
.mod-group summary::-webkit-details-marker { display: none; }
.mod-group summary::before { content: '▸ '; }
.mod-group[open] summary::before { content: '▾ '; }
.mod-group[open] { gap: 10px; }

.toggle-group.compact { gap: 4px; flex-wrap: wrap; }
.toggle-group.compact .toggle-btn { padding: 3px 9px; font-size: 12px; }

.hint {
  color: var(--muted);
  font-size: 11px;
  margin-top: 12px;
  opacity: 0.7;
}

/* ── Layers ── */

.layer-tabs {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 6px;
}

.layer-tab {
  display: flex;
  align-items: stretch;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.15s, background 0.15s;
}
.layer-tab:hover { border-color: var(--accent); }
.layer-tab.selected { border-color: var(--accent); background: var(--accent-dim); }

.layer-tab button {
  background: transparent;
  border: none;
  color: inherit;
  font-family: inherit;
  cursor: pointer;
}

.layer-mute {
  width: 26px;
  flex: none;
  display: flex;
  align-items: center;
  justify-content: center;
}
.layer-mute::before {
  content: '';
  width: 8px; height: 8px;
  border-radius: 50%;
  border: 1px solid var(--muted);
}
.layer-tab.on .layer-mute::before { background: var(--accent); border-color: var(--accent); }

.layer-select {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 6px 8px 6px 0;
  text-align: left;
}
.layer-name { font-size: 12px; font-weight: 600; color: var(--muted); }
.layer-tab.on .layer-name { color: var(--text); }
.layer-tab.selected .layer-name { color: var(--accent); }
.layer-src {
  font-size: 11px;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 100%;
}

.layer-panel {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 4px;
}
.layer-panel.muted { opacity: 0.45; }

/* ── Meter ── */

.meter {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 3px;
  background: rgba(26, 37, 53, 0.6);
}

.meter-fill {
  height: 100%;
  background: var(--accent);
  transform-origin: left;
  transform: scaleX(0);
}

.limit-badge {
  position: absolute;
  top: 8px; right: 10px;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: #ff6060;
  opacity: 0;
}
.limit-badge.on { opacity: 1; }

/* ── Render panel ── */

.render-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.render-spec { text-transform: none; letter-spacing: 0; font-weight: 400; margin-left: 6px; opacity: 0.8; }

.render-row { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }

.duration-select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 8px 10px;
  font: inherit;
  font-size: 13px;
  cursor: pointer;
}

.check-opt {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--muted);
  font-size: 13px;
  cursor: pointer;
  user-select: none;
}
.check-opt input { accent-color: var(--accent); width: 14px; height: 14px; cursor: pointer; }
.check-opt:has(input:disabled) { opacity: 0.4; cursor: default; }

.render-row .export-btn { margin-left: auto; }

/* ── Error ── */

.error-msg {
  background: rgba(255, 80, 80, 0.12);
  border: 1px solid rgba(255, 80, 80, 0.35);
  color: #ff9090;
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 13px;
  line-height: 1.5;
}

/* ── Mobile ── */

@media (max-width: 500px) {
  body { align-items: flex-start; padding: 12px; }

  .visualizer-container { height: 120px; }

  .controls { padding: 12px 16px; }

  .slider-row { grid-template-columns: 66px 1fr 60px; gap: 8px; }

  .app-header { flex-direction: column; }

  .randomize-btn { width: 100%; justify-content: center; }

  .app-footer { flex-direction: column; align-items: stretch; gap: 10px; }

  .play-btn { min-width: unset; width: 100%; }

  .render-row { justify-content: space-between; }
}