/* ============================================
   MULTITRACK PLAYER - STYLES
   ============================================ */

:root {
  /* Colors */
  --color-bg: #0f0f0f;
  --color-bg-secondary: #1a1a1a;
  --color-bg-tertiary: #252525;
  --color-surface: #2a2a2a;
  --color-surface-hover: #333333;
  --color-border: #3a3a3a;
  --color-text: #ffffff;
  --color-text-secondary: #a0a0a0;
  --color-text-muted: #666666;
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;

  /* Track colors */
  --track-drums: #ef4444;
  --track-bass: #f59e0b;
  --track-guitar: #8b5cf6;
  --track-synth: #10b981;
  --track-vocals: #ec4899;
  --track-lead: #3b82f6;

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;

  /* Border radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
}

/* ============================================
   RESET & BASE
   ============================================ */

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  overflow: hidden;
  height: 100vh;
}

#app {
  height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ============================================
   SCREENS
   ============================================ */

.screen {
  display: none;
  height: 100%;
}

.screen.active {
  display: flex;
}

/* ============================================
   LOGIN SCREEN
   ============================================ */

#login-screen,
#register-screen {
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-bg) 0%, #1a1a2e 100%);
}

.login-container {
  width: 100%;
  max-width: 420px;
  padding: var(--spacing-xl);
  background: var(--color-bg-secondary);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--color-border);
}

.login-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--color-primary) 0%, #8b5cf6 100%);
  border-radius: var(--radius-full);
  margin-bottom: var(--spacing-md);
  color: white;
}

.login-header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.login-header .subtitle {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
}

/* Form styles */
.login-form {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
}

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

.form-group input {
  padding: 12px 16px;
  background: var(--color-bg-tertiary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  font-size: 1rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-group input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.form-group input::placeholder {
  color: var(--color-text-muted);
}

.password-input {
  position: relative;
}

.password-input input {
  width: 100%;
  padding-right: 48px;
}

.toggle-password {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  padding: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.toggle-password:hover {
  color: var(--color-text-secondary);
}

.form-options {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  cursor: pointer;
  color: var(--color-text-secondary);
}

.checkbox-label input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--color-primary);
}

.forgot-link {
  color: var(--color-primary);
  text-decoration: none;
}

.forgot-link:hover {
  text-decoration: underline;
}

/* Password requirements */
.password-requirements {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-top: var(--spacing-xs);
}

.password-requirements .req {
  font-size: 0.75rem;
  padding: 2px 8px;
  background: var(--color-bg-tertiary);
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  transition: all var(--transition-fast);
}

.password-requirements .req.valid {
  background: rgba(16, 185, 129, 0.2);
  color: var(--color-success);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: 12px 24px;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-primary {
  background: var(--color-primary);
  color: white;
}

.btn-primary:hover:not(:disabled) {
  background: var(--color-primary-hover);
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--color-surface-hover);
}

.btn-block {
  width: 100%;
}

.btn-sm {
  padding: 8px 16px;
  font-size: 0.875rem;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-loader {
  display: flex;
  align-items: center;
}

.spinner {
  animation: spin 1s linear infinite;
}

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

/* Error message */
.error-message {
  padding: var(--spacing-md);
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid var(--color-error);
  border-radius: var(--radius-md);
  color: var(--color-error);
  font-size: 0.875rem;
  text-align: center;
}

/* Login footer */
.login-footer {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

.login-footer a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
}

.login-footer a:hover {
  text-decoration: underline;
}

/* Demo credentials */
.demo-credentials {
  margin-top: var(--spacing-lg);
  padding: var(--spacing-md);
  background: rgba(59, 130, 246, 0.1);
  border-radius: var(--radius-md);
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  text-align: center;
}

.demo-credentials p {
  margin: 2px 0;
}

.demo-credentials strong {
  color: var(--color-primary);
}

/* ============================================
   APP SCREEN
   ============================================ */

#app-screen {
  flex-direction: column;
}

/* Header */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) var(--spacing-lg);
  background: var(--color-bg-secondary);
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
}

.header-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.logo-small {
  color: var(--color-primary);
}

.header-left h1 {
  font-size: 1.25rem;
  font-weight: 600;
}

.header-right {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.user-name {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

/* Main layout */
.app-main {
  display: flex;
  flex: 1;
  overflow: hidden;
}

/* Sidebar */
.sidebar {
  width: 280px;
  background: var(--color-bg-secondary);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}

.sidebar-header {
  padding: var(--spacing-md) var(--spacing-lg);
  border-bottom: 1px solid var(--color-border);
}

.sidebar-header h2 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.song-list {
  flex: 1;
  overflow-y: auto;
  padding: var(--spacing-sm);
}

.song-item {
  padding: var(--spacing-md);
  background: var(--color-surface);
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 2px solid transparent;
}

.song-item:hover {
  background: var(--color-surface-hover);
}

.song-item.active {
  border-color: var(--color-primary);
  background: rgba(59, 130, 246, 0.1);
}

.song-item-title {
  font-weight: 600;
  margin-bottom: 4px;
}

.song-item-artist {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.song-item-meta {
  display: flex;
  gap: var(--spacing-md);
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* Player area */
.player-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--color-bg);
}

/* Song info */
.song-info {
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg-secondary);
}

.song-info-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl);
  color: var(--color-text-muted);
}

.song-info-placeholder svg {
  margin-bottom: var(--spacing-md);
  opacity: 0.5;
}

.song-info-content {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
}

.song-cover {
  width: 80px;
  height: 80px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
}

.song-details h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.song-details .artist {
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.song-details .meta {
  display: flex;
  gap: var(--spacing-lg);
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* Timeline */
.timeline-container {
  padding: var(--spacing-sm) var(--spacing-lg);
  background: var(--color-bg-tertiary);
  border-bottom: 1px solid var(--color-border);
}

.timeline {
  position: relative;
  height: 30px;
  background: var(--color-surface);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.time-markers {
  display: flex;
  justify-content: space-between;
  padding: 0 var(--spacing-sm);
  font-size: 0.7rem;
  color: var(--color-text-muted);
  line-height: 30px;
}

.playhead {
  position: absolute;
  top: 0;
  left: 0;
  width: 2px;
  height: 100%;
  background: var(--color-primary);
  pointer-events: none;
  z-index: 10;
}

.playhead::before {
  content: '';
  position: absolute;
  top: -4px;
  left: -4px;
  width: 10px;
  height: 10px;
  background: var(--color-primary);
  border-radius: var(--radius-full);
}

/* Tracks container */
.tracks-container {
  flex: 1;
  overflow-y: auto;
  padding: var(--spacing-sm);
}

/* COMPACT TRACK VIEW */
.track {
  display: flex;
  align-items: center;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  margin-bottom: 2px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  height: 48px;
}

.track-controls {
  width: 280px;
  padding: 6px 10px;
  background: var(--color-bg-tertiary);
  border-right: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
  height: 100%;
}

.track-header {
  display: flex;
  align-items: center;
  gap: 6px;
  min-width: 80px;
}

.track-color {
  width: 4px;
  height: 32px;
  border-radius: 2px;
  flex-shrink: 0;
}

.track-name {
  font-weight: 600;
  font-size: 0.8rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 70px;
}

.track-buttons {
  display: flex;
  gap: 2px;
  flex-shrink: 0;
}

.track-btn {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 3px;
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.track-btn:hover {
  background: var(--color-surface-hover);
}

.track-btn.active {
  color: white;
}

.track-btn.mute.active {
  background: var(--color-error);
  border-color: var(--color-error);
}

.track-btn.solo.active {
  background: var(--color-warning);
  border-color: var(--color-warning);
}

.track-volume {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-shrink: 0;
}

.track-volume svg {
  color: var(--color-text-muted);
  flex-shrink: 0;
  width: 14px;
  height: 14px;
}

.track-volume input[type="range"] {
  width: 50px;
}

.track-pan {
  display: none; /* Hidden in compact mode */
}

/* Waveform - COMPACT */
.track-waveform {
  flex: 1;
  position: relative;
  height: 100%;
  min-height: 48px;
  background: var(--color-bg);
}

.waveform-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.track-loading {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg);
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

/* Range inputs */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  height: 4px;
  background: var(--color-surface);
  border-radius: var(--radius-full);
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  background: var(--color-primary);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: transform var(--transition-fast);
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  background: var(--color-primary);
  border-radius: var(--radius-full);
  border: none;
  cursor: pointer;
}

/* Transport controls */
.transport-controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) var(--spacing-lg);
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
}

.transport-left,
.transport-right {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  min-width: 200px;
}

.transport-right {
  justify-content: flex-end;
}

.transport-center {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.time-display {
  font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

.time-separator {
  margin: 0 4px;
  color: var(--color-text-muted);
}

.transport-btn {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  color: var(--color-text);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.transport-btn:hover {
  background: var(--color-surface-hover);
}

.transport-btn.play-btn {
  width: 56px;
  height: 56px;
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.transport-btn.play-btn:hover {
  background: var(--color-primary-hover);
}

.transport-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.master-volume {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.master-volume svg {
  color: var(--color-text-muted);
}

.volume-slider {
  width: 100px;
}

#master-volume-value {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  min-width: 35px;
}

/* Utilities */
.hidden {
  display: none !important;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
  background: var(--color-surface);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-surface-hover);
}

/* Responsive */
@media (max-width: 768px) {
  .sidebar {
    width: 100%;
    position: absolute;
    left: -100%;
    z-index: 100;
    transition: left var(--transition-normal);
  }

  .sidebar.open {
    left: 0;
  }

  .track-controls {
    width: 150px;
  }

  .transport-left,
  .transport-right {
    min-width: auto;
  }
}