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

:root {
  --bg: #111;
  --bg-card: #1a1a1a;
  --bg-elevated: #222;
  --text: #eee;
  --text-muted: #888;
  --accent: #4dabf7;
  --accent-dim: #2b6cb0;
  --danger: #e74c3c;
  --success: #2ecc71;
  --warning: #f39c12;
  --radius: 12px;
  --gap: 16px;
}

html, body {
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  overflow-x: hidden;
  -webkit-text-size-adjust: 100%;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  padding: var(--gap);
  padding-top: env(safe-area-inset-top, 0);
  padding-bottom: env(safe-area-inset-bottom, 0);
}

h1 {
  font-size: 1.3rem;
  font-weight: 600;
  text-align: center;
  margin-bottom: var(--gap);
}

h1 span {
  color: var(--text-muted);
  font-weight: 400;
  font-size: 0.85rem;
}

/* Video */
.video-container {
  position: relative;
  width: 100%;
  max-width: 640px;
  margin: 0 auto var(--gap);
  background: #000;
  border-radius: var(--radius);
  overflow: hidden;
  aspect-ratio: 4/3;
}

.video-container video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.video-placeholder {
  position: absolute;
  top: 0;
  left: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  color: var(--text-muted);
  font-size: 1rem;
  background: #000;
  pointer-events: none;
}

/* QR Code area */
.qr-area {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  margin-bottom: var(--gap);
}

.qr-area canvas,
.qr-area img {
  border-radius: 8px;
}

#qr-container,
#answer-qr-container {
  background: #fff;
  padding: 12px;
  border-radius: 8px;
  display: inline-block;
}

/* QR Scanner */
#qr-scanner,
#response-scanner {
  width: 100%;
  max-width: 400px;
  margin: 0 auto var(--gap);
  border-radius: var(--radius);
  overflow: hidden;
}

#qr-scanner video,
#response-scanner video {
  border-radius: var(--radius);
}

/* Spectrogram - fullscreen layout */
#stream-section {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}

.spectrogram-area {
  flex: 1;
  position: relative;
  min-height: 0;
  background: #000;
  border-radius: 8px;
  overflow: hidden;
}

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

.spectrogram-overlay {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 0.9rem;
  color: var(--text-muted);
  pointer-events: none;
}

.viewer-controls {
  padding-top: 8px;
  flex-shrink: 0;
}

.viewer-controls .status-panel {
  margin-bottom: 0;
}

.viewer-controls .actions {
  margin-bottom: 0;
}

/* Status panel */
.status-panel {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-bottom: var(--gap);
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--bg-elevated);
  border-radius: 20px;
  padding: 6px 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.status-badge .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-muted);
}

.status-badge .dot.green { background: var(--success); }
.status-badge .dot.yellow { background: var(--warning); }
.status-badge .dot.red { background: var(--danger); }

/* Audio level meter */
.audio-meter {
  width: 60px;
  height: 6px;
  background: var(--bg);
  border-radius: 3px;
  overflow: hidden;
}

.audio-meter-fill {
  height: 100%;
  background: var(--success);
  width: 0%;
  transition: width 0.1s;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border: none;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.15s;
  color: #fff;
}

.btn:active {
  opacity: 0.8;
}

.btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

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

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

.btn-secondary {
  background: var(--bg-elevated);
  color: var(--text);
  border: 1px solid #333;
}

.actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--gap);
}

/* Error / info messages */
.message {
  text-align: center;
  padding: 12px;
  border-radius: var(--radius);
  margin-bottom: var(--gap);
  font-size: 0.9rem;
}

.message-error {
  background: rgba(231, 76, 60, 0.15);
  color: var(--danger);
}

.message-info {
  background: rgba(77, 171, 247, 0.15);
  color: var(--accent);
}

.hidden {
  display: none !important;
}

/* Unmute banner */
.unmute-banner {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.3);
  color: #fff;
  padding: 10px 24px;
  border-radius: 24px;
  font-size: 0.95rem;
  cursor: pointer;
  z-index: 10;
  margin: 0;
}

/* Fullscreen overlay button */
.fullscreen-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  background: rgba(0, 0, 0, 0.5);
  border: none;
  color: #fff;
  width: 36px;
  height: 36px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
}

/* Viewer connecting spinner */
.connecting {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  color: var(--text-muted);
}

.spinner {
  width: 32px;
  height: 32px;
  border: 3px solid var(--bg-elevated);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

/* Responsive */
@media (max-width: 480px) {
  body {
    padding: 12px;
  }
  .video-container {
    border-radius: 8px;
  }
}