/* ─── Design Tokens ──────────────────────────────────────────────────────── */
:root {
  --bg:          #070c16;
  --bg-2:        #0d1526;
  --bg-card:     #111d33;
  --border:      #1b2d4a;
  --border-2:    #253d63;
  --accent:      #14b8a6;
  --accent-2:    #818cf8;
  --accent-glow: rgba(20,184,166,0.25);
  --text:        #e2e8f0;
  --text-2:      #94a3b8;
  --text-3:      #475569;
  --success:     #22c55e;
  --warning:     #f59e0b;
  --danger:      #ef4444;
  --radius:      10px;
  --radius-lg:   16px;
  --shadow:      0 4px 24px rgba(0,0,0,0.5);
  --shadow-lg:   0 8px 40px rgba(0,0,0,0.7);
  --font:        'Inter', system-ui, -apple-system, sans-serif;
  --font-mono:   'JetBrains Mono', 'Fira Code', monospace;
  --sidebar-w:   260px;
  --transition:  0.2s ease;
}

/* ─── Reset & Base ────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  overflow-x: hidden;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

button { cursor: pointer; font-family: var(--font); }
input, select, textarea { font-family: var(--font); }

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

/* ─── Layout ─────────────────────────────────────────────────────────────── */
#sidebar {
  width: var(--sidebar-w);
  min-height: 100vh;
  background: var(--bg-2);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: 100;
  overflow-y: auto;
  transition: transform var(--transition);
}

#main {
  margin-left: var(--sidebar-w);
  flex: 1;
  min-width: 0;
  padding: 2rem;
  max-width: 900px;
}

/* ─── Sidebar ─────────────────────────────────────────────────────────────── */
.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 1.5rem 1.25rem 1rem;
  cursor: pointer;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0.5rem;
}
.sidebar-logo svg { flex-shrink: 0; }
.sidebar-logo-text { font-size: 1.1rem; font-weight: 700; letter-spacing: -0.02em; }
.sidebar-logo-text span { color: var(--accent); }

.nav-section-label {
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  padding: 0.75rem 1.25rem 0.25rem;
}

nav ul { list-style: none; padding: 0 0.5rem 1rem; }
.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius);
  color: var(--text-2);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
  user-select: none;
}
.nav-link:hover { background: rgba(255,255,255,0.04); color: var(--text); }
.nav-link.active { background: var(--accent-glow); color: var(--accent); }
.nav-link .nav-icon { width: 18px; text-align: center; font-size: 1rem; flex-shrink: 0; }

.sidebar-footer {
  margin-top: auto;
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border);
  font-size: 0.75rem;
  color: var(--text-3);
}
.sidebar-copyright {
  margin-top: 0.6rem;
  padding-top: 0.6rem;
  border-top: 1px solid var(--border);
  font-size: 0.7rem;
  color: var(--text-3);
}

/* Mobile header */
#mobile-header {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 56px;
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
  z-index: 200;
  align-items: center;
  padding: 0 1rem;
  gap: 12px;
}
#menu-toggle {
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.4rem;
  padding: 4px;
}
.mobile-logo { font-weight: 700; font-size: 1rem; }
.mobile-logo span { color: var(--accent); }

/* ─── Tool Panels ─────────────────────────────────────────────────────────── */
.tool-panel { display: none; animation: fadeIn 0.25s ease; }
.tool-panel.active { display: block; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

.panel-header {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.75rem;
}
.panel-icon {
  width: 52px; height: 52px;
  border-radius: 14px;
  background: var(--accent-glow);
  border: 1px solid rgba(20,184,166,0.3);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem;
  flex-shrink: 0;
}
.panel-header h1 { font-size: 1.5rem; font-weight: 700; letter-spacing: -0.02em; margin-bottom: 0.2rem; }
.panel-desc { color: var(--text-2); font-size: 0.875rem; line-height: 1.5; }

/* ─── Home Panel ─────────────────────────────────────────────────────────── */
.home-hero {
  margin-bottom: 2.5rem;
}
.home-hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 0.75rem;
}
.home-hero h1 .accent { color: var(--accent); }
.home-hero p {
  color: var(--text-2);
  font-size: 1rem;
  line-height: 1.6;
  max-width: 560px;
}

.badge-row { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-top: 1rem; }
.badge {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  background: rgba(20,184,166,0.12);
  color: var(--accent);
  border: 1px solid rgba(20,184,166,0.25);
  letter-spacing: 0.04em;
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1rem;
}

.tool-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  cursor: pointer;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}
.tool-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: 0 8px 32px rgba(20,184,166,0.12);
}
.card-icon { font-size: 1.75rem; margin-bottom: 0.75rem; }
.card-title { font-size: 0.9rem; font-weight: 600; margin-bottom: 0.3rem; }
.card-desc  { font-size: 0.75rem; color: var(--text-2); line-height: 1.5; }

/* ─── Upload / Drop Zone ──────────────────────────────────────────────────── */
.drop-zone {
  border: 2px dashed var(--border-2);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  text-align: center;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
  position: relative;
  margin-bottom: 1.5rem;
}
.drop-zone:hover, .drop-zone.drag-over {
  border-color: var(--accent);
  background: var(--accent-glow);
}
.drop-zone input[type="file"] { display: none; }
.drop-icon { font-size: 2.5rem; margin-bottom: 0.75rem; }
.drop-text  { font-size: 0.9rem; color: var(--text); margin-bottom: 0.3rem; }
.drop-text .browse-link { color: var(--accent); text-decoration: underline; cursor: pointer; }
.drop-hint  { font-size: 0.75rem; color: var(--text-3); }

/* ─── Workspace ───────────────────────────────────────────────────────────── */
.workspace {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.workspace-content { padding: 1.5rem; }

.loading-overlay {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 3rem;
  color: var(--text-2);
  font-size: 0.9rem;
}
.spinner {
  width: 20px; height: 20px;
  border: 2px solid var(--border-2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.error-msg {
  color: var(--danger);
  padding: 1rem 1.5rem;
  font-size: 0.875rem;
}

.file-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--text-2);
  background: var(--bg-2);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 6px;
  margin-bottom: 1rem;
}

/* ─── Waveform Canvas ─────────────────────────────────────────────────────── */
.waveform-wrap {
  position: relative;
  background: #080e1a;
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 1rem;
  border: 1px solid var(--border);
}
.waveform-canvas {
  display: block;
  width: 100%;
  height: 100px;
  cursor: crosshair;
}
.waveform-canvas.tall { height: 140px; }

/* ─── Controls ────────────────────────────────────────────────────────────── */
.controls-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.range-group {
  flex: 1;
  min-width: 180px;
}
.range-group label {
  display: flex;
  justify-content: space-between;
  font-size: 0.78rem;
  color: var(--text-2);
  margin-bottom: 0.35rem;
}
.range-group label strong { color: var(--text); font-family: var(--font-mono); }

input[type="range"] {
  width: 100%;
  height: 4px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--border-2);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg);
  box-shadow: 0 0 6px var(--accent-glow);
  cursor: pointer;
}
input[type="range"]::-moz-range-thumb {
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg);
  cursor: pointer;
}

select {
  background: var(--bg-2);
  border: 1px solid var(--border-2);
  border-radius: 6px;
  color: var(--text);
  padding: 0.45rem 0.75rem;
  font-size: 0.875rem;
  cursor: pointer;
}
select:focus { border-color: var(--accent); }

input[type="number"] {
  background: var(--bg-2);
  border: 1px solid var(--border-2);
  border-radius: 6px;
  color: var(--text);
  padding: 0.45rem 0.75rem;
  font-size: 0.875rem;
  width: 80px;
}
input[type="number"]:focus { border-color: var(--accent); outline: none; }

/* ─── Buttons ────────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1.1rem;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 600;
  border: none;
  transition: background var(--transition), opacity var(--transition), transform var(--transition);
  white-space: nowrap;
}
.btn:hover:not(:disabled) { transform: translateY(-1px); }
.btn:active:not(:disabled) { transform: none; }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }

.btn-primary {
  background: var(--accent);
  color: #000;
}
.btn-primary:hover:not(:disabled) { background: #0d9488; }

.btn-secondary {
  background: var(--bg-2);
  color: var(--text);
  border: 1px solid var(--border-2);
}
.btn-secondary:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }

.btn-ghost {
  background: transparent;
  color: var(--text-2);
  border: 1px solid var(--border);
  padding: 0.4rem 0.8rem;
  font-size: 0.8rem;
}
.btn-ghost:hover:not(:disabled) { color: var(--text); border-color: var(--border-2); }
.btn-ghost:disabled { opacity: 0.35; }

.btn-icon {
  background: none;
  border: none;
  color: var(--text-3);
  padding: 4px 6px;
  font-size: 0.85rem;
  border-radius: 4px;
  transition: color var(--transition);
}
.btn-icon:hover { color: var(--danger); }

.btn-row {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

/* ─── Stats & Info ────────────────────────────────────────────────────────── */
.stat-row {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 0.75rem;
  margin-bottom: 1rem;
}
.stat-box {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.75rem;
}
.stat-label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.07em; color: var(--text-3); margin-bottom: 0.3rem; }
.stat-value { font-size: 1rem; font-weight: 700; font-family: var(--font-mono); color: var(--text); }
.stat-value.accent { color: var(--accent); }

.info-text {
  font-size: 0.8rem;
  color: var(--text-2);
  padding: 0.5rem 0;
  line-height: 1.5;
}
.info-text strong { color: var(--accent); }

/* ─── Track List (Merger) ─────────────────────────────────────────────────── */
.track-list {
  list-style: none;
  margin-bottom: 1rem;
}
.track-item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.6rem 0.75rem;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  margin-bottom: 0.4rem;
  font-size: 0.85rem;
  transition: border-color var(--transition);
}
.track-item.drag-over { border-color: var(--accent); }
.track-item.dragging  { opacity: 0.5; }
.track-drag { color: var(--text-3); cursor: grab; font-size: 1rem; }
.track-name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.track-dur  { font-family: var(--font-mono); font-size: 0.78rem; color: var(--text-2); flex-shrink: 0; }

/* ─── Editor toolbar ─────────────────────────────────────────────────────── */
.editor-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding: 0.75rem;
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
}
.toolbar-group {
  display: flex;
  gap: 0.35rem;
  padding-right: 0.6rem;
  border-right: 1px solid var(--border);
}
.toolbar-group:last-child { border-right: none; }

.editor-info-bar {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 0.6rem 0.75rem;
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
  font-size: 0.78rem;
  color: var(--text-2);
}
.editor-info-bar span { font-family: var(--font-mono); color: var(--text); }

.gain-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.gain-row label { font-size: 0.78rem; color: var(--text-2); white-space: nowrap; }

/* ─── Divider / Section labels ────────────────────────────────────────────── */
.section-label {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--text-3);
  margin-bottom: 0.5rem;
}

hr.divider { border: none; border-top: 1px solid var(--border); margin: 1.25rem 0; }

/* ─── Playback row ───────────────────────────────────────────────────────── */
.playback-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}
.time-display {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--text-2);
}
.time-display .current { color: var(--text); }

/* ─── Export row ─────────────────────────────────────────────────────────── */
.export-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  margin-top: 1rem;
}

/* ─── Notes / alerts ─────────────────────────────────────────────────────── */
.note {
  display: flex;
  gap: 0.6rem;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  font-size: 0.82rem;
  line-height: 1.5;
  margin-bottom: 1rem;
}
.note-info    { background: rgba(129,140,248,0.08); border: 1px solid rgba(129,140,248,0.2); color: #a5b4fc; }
.note-warning { background: rgba(245,158,11,0.08);  border: 1px solid rgba(245,158,11,0.2);  color: #fcd34d; }
.note-icon { flex-shrink: 0; }

/* ─── Checkbox ────────────────────────────────────────────────────────────── */
.checkbox-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  cursor: pointer;
}
input[type="checkbox"] {
  accent-color: var(--accent);
  width: 16px; height: 16px;
  cursor: pointer;
}

/* ─── Responsive ──────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
  #sidebar {
    transform: translateX(-100%);
    box-shadow: var(--shadow-lg);
  }
  #sidebar.open { transform: translateX(0); }
  #main { margin-left: 0; padding: 1rem; padding-top: 72px; }
  #mobile-header { display: flex; }
  .tools-grid { grid-template-columns: repeat(2, 1fr); }
  .stat-row { grid-template-columns: repeat(2, 1fr); }
  .export-row { flex-direction: column; align-items: stretch; }
  .export-row .btn { width: 100%; justify-content: center; }
}

@media (max-width: 440px) {
  .tools-grid { grid-template-columns: 1fr 1fr; }
  .editor-toolbar { gap: 0.25rem; }
  .toolbar-group { flex-wrap: wrap; }
}

/* ─── Scrollbar ───────────────────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border-2); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-3); }

/* ─── Utility ─────────────────────────────────────────────────────────────── */
[hidden] { display: none !important; }
.text-muted { color: var(--text-2); }
.text-accent { color: var(--accent); }
.text-mono { font-family: var(--font-mono); }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }