html,
body {
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background: #0b0f1a;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.viewer-shell {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #0b0f1a;
}

#canvas {
  width: 100%;
  height: 100%;
  display: block;
  background: #0b0f1a;
  touch-action: none;
  user-select: none;
}

.viewer-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  background: rgba(11, 15, 26, 0.5);
  color: #f8fafc;
  text-align: center;
  padding: 20px;
  transition: opacity 160ms ease;
}

.viewer-overlay.is-hidden {
  opacity: 0;
  pointer-events: none;
}

.viewer-spinner {
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 4px solid rgba(148, 163, 184, 0.35);
  border-top-color: #3b9ce8;
  animation: viewer-spin 0.8s linear infinite;
}

.viewer-status {
  margin: 0;
  font-size: 18px;
  line-height: 1.35;
  font-weight: 500;
}

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