/* =============================================
   CSS CUSTOM PROPERTIES
   ============================================= */
:root {
  /* Background Colors */
  --bg-page: #111111;
  --bg-container: #1c1c1c;
  --bg-section: #242424;
  --bg-input: #2e2e2e;
  --bg-hover: rgba(255,255,255,0.05);

  /* Accent Colors */
  --accent-primary: #e94560;
  --accent-primary-hover: #ff6b6b;
  --accent-secondary: #00d9ff;
  --accent-secondary-hover: #40e0ff;
  --accent-success: #00c853;
  --accent-success-hover: #00e676;
  --accent-warning: #ffab00;
  --accent-warning-hover: #ffc107;
  --accent-danger: #ff1744;
  --accent-danger-hover: #ff5252;
  --accent-neutral: #4a5568;

  /* Text Colors */
  --text-primary: #ffffff;
  --text-secondary: rgba(255,255,255,0.7);
  --text-muted: rgba(255,255,255,0.5);

  /* Borders & Shadows */
  --border-color: rgba(255,255,255,0.1);
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.5);

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
}

/* =============================================
   BASE STYLES
   ============================================= */
* {
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  margin: 0;
  padding: var(--space-2);
  background: var(--bg-page);
  color: var(--text-primary);
  min-height: 100vh;
}

.container {
  max-width: none;
  margin: 0 auto;
  background: var(--bg-container);
  padding: var(--space-3);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

/* =============================================
   TYPOGRAPHY
   ============================================= */
.page-header {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  margin-bottom: var(--space-2);
}

.page-header .github-link {
  position: absolute;
  right: 0;
  margin: 0;
  padding: var(--space-1) var(--space-2);
  font-size: 0.8rem;
}

h1 {
  color: var(--text-secondary);
  font-size: 2rem;
  font-weight: 700;
  margin: 0;
  text-align: center;
}

h2 {
  color: var(--text-primary);
  font-size: 1.25rem;
  font-weight: 600;
  margin: var(--space-6) 0 var(--space-4) 0;
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--border-color);
}

p {
  color: var(--text-secondary);
  margin: 0 0 var(--space-4) 0;
}

a {
  color: var(--accent-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-secondary-hover);
}

strong {
  color: var(--text-primary);
}

/* =============================================
   FORM CONTROLS
   ============================================= */
label {
  display: inline-block;
  margin-bottom: var(--space-1);
  color: var(--text-secondary);
  font-size: 0.875rem;
}

select, input[type="text"], input[type="number"] {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  padding: var(--space-2) var(--space-3);
  font-size: 0.875rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

select:focus, input[type="text"]:focus, input[type="number"]:focus {
  outline: none;
  border-color: var(--accent-secondary);
  box-shadow: 0 0 0 3px rgba(0, 217, 255, 0.2);
}

input[type="range"] {
  -webkit-appearance: none;
  background: var(--bg-input);
  border-radius: 999px;
  height: 6px;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  background: var(--accent-secondary);
  border-radius: 50%;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 0 8px var(--accent-secondary);
}

input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  background: var(--accent-secondary);
  border-radius: 50%;
  border: none;
  cursor: pointer;
}

/* =============================================
   BUTTONS
   ============================================= */
button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-primary);
  background: var(--accent-primary);
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
}

button:hover:not(:disabled) {
  background: var(--accent-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

button:active:not(:disabled) {
  transform: translateY(0);
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

button.btn-secondary {
  background: var(--accent-neutral);
}

button.btn-secondary:hover:not(:disabled) {
  background: #5a6a7a;
}

button.btn-success {
  background: var(--accent-success);
}

button.btn-success:hover:not(:disabled) {
  background: var(--accent-success-hover);
}

button.btn-danger {
  background: var(--accent-danger);
}

button.btn-danger:hover:not(:disabled) {
  background: var(--accent-danger-hover);
}

button.btn-warning {
  background: var(--accent-warning);
  color: #000;
}

button.btn-warning:hover:not(:disabled) {
  background: var(--accent-warning-hover);
}

button.btn-info {
  background: var(--accent-secondary);
  color: #000;
}

button.btn-info:hover:not(:disabled) {
  background: var(--accent-secondary-hover);
}

.btn-sm, select.btn-sm {
  padding: var(--space-1) var(--space-2);
  font-size: 0.75rem;
}

.btn-icon {
  background: transparent;
  border: none;
  padding: 2px 4px;
  font-size: 0.9rem;
  cursor: pointer;
  opacity: 0.6;
  transition: opacity 0.15s ease;
  line-height: 1;
}

.btn-icon.btn-xs {
  font-size: 0.7rem;
  padding: 1px 2px;
}

.btn-icon:hover:not(:disabled) {
  opacity: 1;
  background: transparent;
  transform: none;
  box-shadow: none;
}

/* Copy toast */
.copy-toast {
  position: fixed;
  bottom: var(--space-5);
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--bg-section);
  color: var(--text-primary);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  font-size: 0.875rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 1000;
}

.copy-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Instrument panel header — hidden in narrow, shown in widescreen */
.instrument-header {
  display: none;
}

/* (Collapsible sections replaced by tab interface) */

/* =============================================
   NOTICE
   ============================================= */
.notice {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4);
  background: rgba(255, 171, 0, 0.1);
  border: 1px solid rgba(255, 171, 0, 0.3);
  border-left: 4px solid var(--accent-warning);
  border-radius: var(--radius-md);
  margin: var(--space-5) 0;
  color: var(--text-secondary);
}

.notice strong {
  color: var(--accent-warning);
}

/* =============================================
   PIANO KEYBOARD
   ============================================= */
.piano-section {
  padding: var(--space-4);
  background: var(--bg-section);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.piano-section .controls-panel {
  margin-top: var(--space-3);
  background: transparent;
  border: none;
  padding: var(--space-3) 0 0 0;
}

.piano {
  display: flex;
  justify-content: center;
  padding: var(--space-4);
  background: linear-gradient(180deg, #2a2a2a 0%, #1e1e1e 100%);
  border-radius: var(--radius-lg);
  box-shadow: inset 0 2px 4px rgba(0,0,0,0.3), var(--shadow-md);
}

/* =============================================
   OSCILLOSCOPE
   ============================================= */
.oscilloscope-container {
  margin-top: var(--space-3);
  padding: var(--space-3);
  background: linear-gradient(180deg, #1e1e1e 0%, #2a2a2a 100%);
  border-radius: var(--radius-lg);
  box-shadow: inset 0 2px 4px rgba(0,0,0,0.3);
}

.oscilloscope-container canvas {
  display: block;
  width: 100%;
  height: 100px;
  border-radius: var(--radius-sm);
  background: #0a0a0a;
}

.key {
  position: relative;
  width: 44px;
  height: 140px;
  background: linear-gradient(180deg, #f8f9fa 0%, #e9ecef 100%);
  border: 1px solid #bbb;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  margin: 0 1px;
  cursor: pointer;
  transition: all 0.08s ease-out;
  box-shadow: 0 4px 0 rgba(0,0,0,0.2), 0 6px 8px rgba(0,0,0,0.15);
}

.key:hover {
  background: linear-gradient(180deg, #fff 0%, #f0f0f0 100%);
}

.key.pressed {
  background: linear-gradient(180deg, #dee2e6 0%, #ced4da 100%);
  transform: translateY(2px);
  box-shadow: 0 2px 0 rgba(0,0,0,0.2), 0 3px 4px rgba(0,0,0,0.1);
}

.key.black {
  width: 28px;
  height: 90px;
  background: linear-gradient(180deg, #343a40 0%, #212529 100%);
  border: none;
  margin-left: -14px;
  margin-right: -14px;
  z-index: 2;
  box-shadow: 0 4px 0 rgba(0,0,0,0.4), 0 6px 8px rgba(0,0,0,0.3);
}

.key.black:hover {
  background: linear-gradient(180deg, #495057 0%, #343a40 100%);
}

.key.black.pressed {
  background: linear-gradient(180deg, #495057 0%, #343a40 100%);
  transform: translateY(2px);
  box-shadow: 0 1px 0 rgba(0,0,0,0.4);
}

/* =============================================
   CONTROLS PANEL
   ============================================= */
.controls-panel {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-4);
  margin-top: var(--space-4);
  padding: var(--space-4);
  background: var(--bg-section);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.control-group {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.control-group label {
  margin: 0;
}

/* =============================================
   TABS
   ============================================= */
.tab-nav {
  display: flex;
  gap: var(--space-1);
  padding: var(--space-2);
  background: var(--bg-section);
  border-radius: var(--radius-lg);
  margin-top: var(--space-4);
  overflow-x: auto;
}

.tab-btn {
  padding: var(--space-3) var(--space-4);
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.tab-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  transform: none;
  box-shadow: none;
}

.tab-btn.active {
  background: var(--accent-primary);
  color: var(--text-primary);
}

.tab-btn.active:hover {
  background: var(--accent-primary-hover);
}

.tab-content {
  display: none;
  padding: var(--space-4);
  background: var(--bg-section);
  border-radius: var(--radius-lg);
  margin-top: var(--space-3);
  border: 1px solid var(--border-color);
}

.tab-content.active {
  display: block;
}

.tab-help {
  font-size: 0.875rem;
  color: var(--text-secondary);
  padding: var(--space-3);
  background: var(--bg-input);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all 0.2s ease;
}

.tab-help:hover,
.tab-help:focus-visible {
  background: var(--bg-hover);
}

.tab-help:focus-visible {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 2px;
}

.tab-help::after {
  content: '';
  width: 8px;
  height: 8px;
  border-right: 2px solid var(--text-muted);
  border-bottom: 2px solid var(--text-muted);
  transform: rotate(-45deg);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.tab-help.expanded::after {
  transform: rotate(45deg);
}

.tab-help-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, margin 0.3s ease;
}

.tab-help-content.show {
  max-height: 2000px;
  overflow-y: auto;
  margin-bottom: var(--space-4);
}

.tab-help-content ul {
  margin: var(--space-3) 0 0 0;
  padding-left: var(--space-5);
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.tab-help-content li {
  margin-bottom: var(--space-2);
}

/* =============================================
   CLIPS SECTION
   ============================================= */
.clips-section {
  margin-top: var(--space-4);
  padding: var(--space-4);
  background: var(--bg-section);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.clips-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-3);
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--border-color);
}

.clips-header strong {
  font-size: 1rem;
}

.storage-indicator {
  font-size: 0.75rem;
  padding: var(--space-1) var(--space-2);
  background: var(--bg-input);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
}

.clip-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3);
  background: var(--bg-container);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin: var(--space-2) 0;
  transition: border-color 0.2s ease;
}

.clip-item:hover {
  border-color: var(--accent-secondary);
}

.clip-item audio {
  flex: 1;
  height: 36px;
  min-width: 150px;
}

/* =============================================
   INSTRUMENT GENERATOR
   ============================================= */
.generator-row {
  display: flex;
  gap: var(--space-3);
  align-items: center;
  flex-wrap: wrap;
  justify-content: space-between;
}

.generator-row button {
  white-space: nowrap;
}

.type-radios {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-2);
  margin: var(--space-3) 0;
  padding: var(--space-3);
  background: var(--bg-section);
  border-radius: var(--radius-md);
}

.type-radio {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2);
  background: var(--bg-input);
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.2s ease;
  border: 1px solid transparent;
  text-align: center;
}

.type-radio:hover {
  background: var(--bg-hover);
  border-color: var(--border-color);
}

.type-radio:has(input:checked) {
  background: var(--accent-primary);
  color: var(--text-primary);
  border-color: var(--accent-primary);
}

.type-radio input {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.type-radio:focus-within {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 2px;
}

.type-icon {
  font-size: 2rem;
  line-height: 1;
}

.type-label {
  font-size: 0.7rem;
  line-height: 1.2;
}

.json-section-header {
  margin-bottom: var(--space-3);
}

/* =============================================
   INSTRUMENT VISUALIZER
   ============================================= */
.instrument-viz {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.osc-card {
  background: var(--bg-container);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-3);
  transition: border-color 0.2s ease;
}

.osc-card:hover {
  border-color: var(--accent-secondary);
}

.osc-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
  flex-wrap: wrap;
}

.osc-label {
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--text-primary);
}

.osc-badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 600;
  background: var(--bg-input);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}

.osc-badge.waveform {
  background: var(--accent-primary);
  color: var(--text-primary);
  border-color: var(--accent-primary);
}

.osc-badge.filter {
  background: rgba(255, 171, 0, 0.15);
  color: var(--accent-warning);
  border-color: rgba(255, 171, 0, 0.3);
}

.osc-badge.mod {
  background: rgba(0, 217, 255, 0.1);
  color: var(--accent-secondary);
  border-color: rgba(0, 217, 255, 0.2);
}

.osc-badge.fx {
  background: rgba(0, 200, 83, 0.1);
  color: var(--accent-success);
  border-color: rgba(0, 200, 83, 0.2);
}

.osc-envelopes {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.env-block {
  flex: 1;
  min-width: 180px;
}

.env-label {
  font-size: 0.7rem;
  color: var(--text-muted);
  margin-bottom: var(--space-1);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.adsr-canvas {
  display: block;
  width: 100%;
  height: 64px;
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
}

.mod-badges {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.fx-chain {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  align-items: center;
  padding: var(--space-3);
  background: var(--bg-container);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
}

.fx-chain-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-right: var(--space-2);
}

/* =============================================
   FM MATRIX VISUALIZER
   ============================================= */
.fm-matrix-grid {
  margin-top: var(--space-2);
}

.fm-matrix-label {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-muted);
  padding: 4px;
  text-align: center;
}

.fm-matrix-cell {
  font-size: 0.7rem;
  font-family: 'Consolas', 'Monaco', monospace;
  padding: 4px;
  text-align: center;
  border-radius: var(--radius-sm);
  background: var(--bg-input);
  color: var(--text-secondary);
}

/* =============================================
   ROTARY KNOB CONTROL
   ============================================= */
.fm-knob-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.fm-knob {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--bg-input);
  border: 2px solid var(--border-color);
  position: relative;
  cursor: grab;
  user-select: none;
  touch-action: none;
  transition: border-color 0.15s ease;
}

.fm-knob:hover {
  border-color: var(--accent-secondary);
}

.fm-knob.active {
  cursor: grabbing;
  border-color: var(--accent-secondary);
  box-shadow: 0 0 8px rgba(0, 217, 255, 0.3);
}

.fm-knob-indicator {
  position: absolute;
  width: 2px;
  height: 9px;
  background: var(--accent-secondary);
  left: 50%;
  top: 2px;
  transform-origin: 50% 12px;
  border-radius: 1px;
  pointer-events: none;
}

.fm-knob-wrapper {
  display: flex;
  gap: 4px;
  justify-content: center;
}

.fm-knob-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.fm-knob-label {
  font-size: 0.55rem;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.fm-knob-value {
  font-size: 0.55rem;
  color: var(--text-muted);
  font-family: 'Consolas', 'Monaco', monospace;
  text-align: center;
  width: 32px;
  padding: 1px 2px;
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  outline: none;
  box-sizing: border-box;
}

.fm-knob-value:hover {
  border-color: var(--border-color);
}

.fm-knob-value:focus {
  background: var(--bg-input);
  border-color: var(--accent-secondary);
  color: var(--text-primary);
}

/* FM Matrix Editor in Designer */
.fm-matrix-editor {
  display: grid;
  gap: 4px;
  padding: var(--space-2);
  background: var(--bg-section);
  border-radius: var(--radius-md);
  justify-items: center;
  align-items: center;
}

.fm-matrix-editor-label {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-muted);
  text-align: center;
}

/* =============================================
   PRESETS
   ============================================= */
.preset-section {
  margin-bottom: var(--space-5);
}

.preset-accordion {
  margin-top: var(--space-4);
}

.preset-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-bottom: var(--space-4);
}

.preset-tab {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  background: var(--bg-section);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.preset-tab:hover {
  color: var(--text-primary);
  background: var(--bg-hover);
  border-color: var(--accent-secondary);
}

.preset-tab.active {
  color: #000;
  background: var(--accent-secondary);
  border-color: var(--accent-secondary);
}

.preset-tab.active .preset-tab-count {
  background: rgba(0, 0, 0, 0.3);
  color: #fff;
}

.preset-tab-icon {
  font-size: 1em;
}

.preset-tab-count {
  background: var(--accent-secondary);
  color: #000;
  padding: 1px 6px;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 600;
}

.preset-tab-panel {
  padding: var(--space-3) 0;
}

.preset-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: var(--space-3);
}

.channel-preset-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
  margin-top: var(--space-3);
}

.preset-item {
  display: flex;
  flex-direction: column;
  padding: var(--space-3);
  background: var(--bg-container);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  gap: var(--space-2);
  transition: all 0.2s ease;
}

.preset-item:hover {
  border-color: var(--accent-secondary);
  box-shadow: var(--shadow-sm);
}

.preset-item-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.preset-controls {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  width: 100%;
  margin-top: var(--space-2);
  flex-wrap: wrap;
}

.preset-controls label {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin: 0;
}

.preset-volume {
  width: 80px;
}

.preset-name {
  flex: 1;
  cursor: pointer;
  font-weight: 500;
  color: var(--text-primary);
  transition: color 0.2s ease;
}

.preset-name:hover,
.preset-name:focus-visible {
  color: var(--accent-secondary);
}

.preset-name:focus-visible {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.preset-seed {
  color: var(--text-muted);
  font-family: 'Consolas', 'Monaco', monospace;
  font-size: 0.75rem;
}

.preset-btn {
  padding: var(--space-1) var(--space-2);
  font-size: 0.7rem;
  margin: 0;
}

.preset-btn.copy {
  background: var(--accent-secondary);
  color: #000;
}

.preset-btn.rename {
  background: var(--accent-warning);
  color: #000;
}

.preset-btn.delete {
  background: var(--accent-danger);
}

.save-preset-row {
  display: flex;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.save-preset-row input {
  flex: 1;
}

.no-presets {
  color: var(--text-muted);
  font-style: italic;
  padding: var(--space-4);
  text-align: center;
}

/* =============================================
   MIDI CHANNELS
   ============================================= */
.channel-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-2);
}

@media (max-width: 1100px) {
  .channel-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 900px) {
  .channel-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.channel-row {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-3);
  background: var(--bg-container);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
}

.channel-row:hover {
  border-color: var(--accent-secondary);
}

.channel-row.active {
  border-left: 3px solid var(--accent-secondary);
  background: var(--bg-hover);
}

.channel-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.channel-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.channel-buttons {
  display: flex;
  gap: var(--space-2);
}

.channel-activity {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--bg-input);
  flex-shrink: 0;
  transition: all 0.15s ease;
  margin-left: auto;
}

.channel-activity.on {
  background: var(--accent-success);
  box-shadow: 0 0 8px var(--accent-success);
}

.channel-activity.off {
  background: var(--accent-danger);
  box-shadow: 0 0 8px var(--accent-danger);
}

.channel-input {
  width: 100%;
  font-family: 'Consolas', 'Monaco', monospace;
  font-size: 0.75rem;
}

.set-active-btn {
  background: var(--accent-secondary);
  color: #000;
  margin: 0;
}

.set-active-btn:hover:not(:disabled) {
  background: var(--accent-secondary-hover);
}

.set-active-btn:disabled,
.set-active-btn[aria-disabled="true"] {
  background: var(--accent-success);
  opacity: 1;
  cursor: default;
}

.set-active-btn[aria-disabled="true"]:hover {
  transform: none;
  box-shadow: none;
}

.clear-btn {
  background: var(--accent-danger);
  margin: 0;
}

.clear-btn[aria-disabled="true"] {
  opacity: 0.6;
  cursor: default;
}

.clear-btn[aria-disabled="true"]:hover {
  transform: none;
  box-shadow: none;
}

/* =============================================
   INSTRUMENT JSON
   ============================================= */
#instrumentJson {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  color: var(--text-secondary);
  font-family: 'Consolas', 'Monaco', monospace;
  font-size: 0.8rem;
  white-space: pre-wrap;
  word-wrap: break-word;
  overflow: auto;
  max-height: 400px;
  margin: var(--space-3) 0 0 0;
}

/* =============================================
   CODE SAMPLE
   ============================================= */
.code-sample-header {
  margin-bottom: var(--space-3);
}

.code-sample {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  color: var(--text-secondary);
  font-family: 'Consolas', 'Monaco', monospace;
  font-size: 0.8rem;
  white-space: pre-wrap;
  word-wrap: break-word;
  overflow: auto;
  max-height: 400px;
  margin: 0;
}

.code-sample:focus-visible {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 2px;
}

h1:focus-visible,
h2:focus-visible,
h3:focus-visible,
p[tabindex]:focus-visible,
ul[tabindex]:focus-visible,
strong[tabindex]:focus-visible,
label[tabindex]:focus-visible,
.channel-label:focus-visible,
.preset-seed:focus-visible,
#instrumentHeaderSeed:focus-visible,
#instrumentTypeLabel:focus-visible,
.notice:focus-visible,
.osc-card:focus-visible,
.env-block:focus-visible,
.mod-badges:focus-visible,
.fx-chain:focus-visible,
.tab-help-content:focus-visible,
[role="status"]:focus-visible {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* =============================================
   FOOTER
   ============================================= */
.github-link {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  color: var(--text-secondary);
  margin-top: var(--space-5);
  padding: var(--space-3) var(--space-4);
  background: var(--bg-section);
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
}

.github-link:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.github-link img {
  width: 24px;
  height: 24px;
  margin-right: var(--space-3);
  filter: invert(1);
}

/* =============================================
   UTILITY CLASSES
   ============================================= */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

.divider {
  border-top: 1px solid var(--border-color);
  margin: var(--space-4) 0;
  padding-top: var(--space-4);
}

/* =============================================
   ANIMATIONS
   ============================================= */
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

@keyframes glow {
  0%, 100% { box-shadow: 0 0 4px currentColor; }
  50% { box-shadow: 0 0 12px currentColor; }
}

.recording-pulse {
  animation: pulse 1s infinite;
}

/* =============================================
   RESPONSIVE
   ============================================= */
@media (max-width: 768px) {
  body {
    padding: var(--space-1);
  }

  .container {
    padding: var(--space-2);
    border-radius: var(--radius-lg);
  }

  h1 {
    font-size: 1.5rem;
  }

  .controls-panel {
    flex-direction: column;
    align-items: stretch;
  }

  .control-group {
    justify-content: space-between;
  }

  .piano {
    overflow-x: auto;
    justify-content: flex-start;
    padding: var(--space-3);
  }

  .key {
    width: 36px;
    height: 120px;
    flex-shrink: 0;
  }

  .key.black {
    width: 24px;
    height: 75px;
    margin-left: -12px;
    margin-right: -12px;
  }

  .channel-grid {
    grid-template-columns: 1fr;
  }

  .channel-preset-grid {
    grid-template-columns: 1fr;
  }

  .clip-item {
    flex-wrap: wrap;
  }

  .clip-item audio {
    width: 100%;
    order: 10;
    margin-top: var(--space-2);
  }
}

@media (max-width: 480px) {
  .save-preset-row {
    flex-direction: column;
  }

  .generator-row {
    flex-direction: column;
  }

  .generator-row button {
    margin-top: 0;
  }

  .type-radios {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-1);
  }

  .type-icon {
    font-size: 1.5rem;
  }

  .type-label {
    font-size: 0.6rem;
  }

  .osc-envelopes {
    flex-direction: column;
  }

  .design-env-row-container {
    flex-direction: column;
  }

  .design-env-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-1);
  }

  .design-env-col {
    flex: unset;
  }
}

/* =============================================
   WIDESCREEN: TWO-COLUMN WITH COLLAPSIBLE SIDEBAR
   ============================================= */
@media (min-width: 1400px) {
  .container {
    max-width: none;
  }

  .tab-nav {
    display: none;
  }

  .tab-content {
    display: block !important;
    margin-top: 0;
  }

  /* Instrument panel header */
  .instrument-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-3);
    padding-bottom: var(--space-3);
    border-bottom: 1px solid var(--border-color);
  }

  .instrument-header-seed {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    font-size: 0.85rem;
    font-weight: 400;
    color: var(--text-secondary);
    font-family: 'Consolas', 'Monaco', monospace;
  }

  .tab-panels {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
    margin-top: var(--space-4);
    align-items: start;
  }

  /* Side panels container */
  .side-panels {
    display: flex;
    flex-direction: column;
    gap: 0;
  }

  /* Side panel tab bar (injected by JS) */
  .side-panel-tabs {
    display: flex;
    border-bottom: 2px solid var(--border-color);
  }

  .side-panel-tab {
    flex: 1;
    padding: var(--space-2) var(--space-3);
    background: transparent;
    color: var(--text-secondary);
    border: none;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
  }

  .side-panel-tab:hover {
    color: var(--text-primary);
    background: var(--bg-section);
  }

  .side-panel-tab.active {
    color: var(--accent-secondary);
    border-bottom-color: var(--accent-secondary);
  }

  /* Side panel body (content wrapper injected by JS) */
  .side-panel-body {
    padding: var(--space-4);
  }

  /* Hide original tab-content inside side-panels — JS wraps content into .side-panel-body */
  .side-panels > .tab-content {
    display: none !important;
  }
}

/* Focus sentinel — visually hidden element at end of tab panels for focus wrapping */
.focus-sentinel {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* =============================================
   INSTRUMENT DESIGN TAB
   ============================================= */
.design-osc {
  background: var(--bg-container);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-3);
  transition: border-color 0.2s ease;
}

.design-osc:hover {
  border-color: var(--accent-secondary);
}

.design-osc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: var(--space-3);
  cursor: pointer;
  user-select: none;
  border-bottom: 1px solid var(--border-color);
}

.design-osc-header:hover {
  background: var(--bg-hover);
}

.design-osc-header-left {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
  flex: 1;
}

.design-osc-chevron {
  font-size: 0.7rem;
  color: var(--text-muted);
  transition: transform 0.15s ease;
}

.design-osc-body {
  padding: var(--space-3);
}

.design-osc-body.disabled {
  opacity: 0.35;
  pointer-events: none;
}

.design-osc.osc-disabled {
  opacity: 0.7;
  border-color: var(--border-color);
}

.design-osc.osc-disabled .design-osc-header {
  background: var(--bg-hover);
}

.design-osc-enable {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 0.75rem;
  color: var(--text-muted);
  cursor: pointer;
  user-select: none;
}

.design-osc-enable input[type="checkbox"] {
  cursor: pointer;
}

.design-row {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
  align-items: flex-end;
  margin-bottom: var(--space-3);
}

.design-control {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 0;
}

.design-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
}

.design-input {
  width: 72px;
  height: 28px;
  padding: 0 var(--space-2);
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.8rem;
  font-family: 'Consolas', 'Monaco', monospace;
  box-sizing: border-box;
  -moz-appearance: textfield;
}

.design-input::-webkit-outer-spin-button,
.design-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.design-input:focus {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 1px;
}

.design-select {
  height: 28px;
  padding: 0 var(--space-2);
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.8rem;
  cursor: pointer;
  box-sizing: border-box;
}

.design-select:focus {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 1px;
}

/* Envelope editor — side-by-side tiles like instrument visualizer */
.design-env-row-container {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-3);
}

.design-env-tile {
  flex: 1;
  min-width: 0;
  overflow: hidden;
}

.design-env-label {
  font-size: 0.7rem;
  color: var(--text-muted);
  margin-bottom: var(--space-1);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}

.design-env-canvas {
  display: block;
  width: 100%;
  height: 64px;
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-2);
}

.design-env-grid {
  display: flex;
  gap: var(--space-1);
}

.design-env-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  flex: 1;
}

.design-env-stage {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-muted);
  text-align: center;
}

.design-env-col .design-input {
  width: 100%;
  min-width: 0;
  font-size: 0.7rem;
  padding: 2px 3px;
  text-align: center;
  -moz-appearance: textfield;
}

.design-env-col .design-input::-webkit-outer-spin-button,
.design-env-col .design-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

input.design-input-flat {
  -moz-appearance: textfield;
}

input.design-input-flat::-webkit-outer-spin-button,
input.design-input-flat::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

/* Tile-based toggle sections — always visible, greyed when disabled */
.design-tiles-row {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
  margin-bottom: var(--space-3);
}

.design-tile {
  flex: 1;
  min-width: 130px;
  background: var(--bg-section);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-2);
  transition: border-color 0.2s ease;
}

.design-tile.enabled {
  border-color: var(--accent-secondary);
  background: var(--bg-container);
}

.design-tile-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  margin-bottom: var(--space-2);
  user-select: none;
}

.design-tile-header input[type="checkbox"] {
  accent-color: var(--accent-secondary);
  cursor: pointer;
}

.design-tile-header:hover {
  color: var(--text-primary);
}

.design-tile-content {
  transition: opacity 0.15s ease;
}

.design-tile-content.disabled {
  opacity: 0.3;
  pointer-events: none;
}

.design-tile-content .design-row {
  margin-bottom: 0;
}

.design-tile-content .design-control {
  min-width: 0;
}

.design-tile-content .design-input {
  width: 60px;
  font-size: 0.75rem;
}

.design-tile-content .design-select {
  font-size: 0.75rem;
}

/* Focus-visible for design elements */
.design-osc:focus-visible,
.design-osc-header:focus-visible {
  outline: 2px solid var(--accent-secondary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}