.debug-mode, .debug-mode *, .debug-mode *::before, .debug-mode *::after {
  outline: 1px solid var(--debug-colour, red);
  position: relative;
}
.debug-info {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  font-family: 'Fira Code', monospace;
  font-size: 1rem;
  white-space: nowrap;
}
.debug-info.over { top: -2.5rem; }
.debug-info.under { bottom: -2.5rem; }
.debug-info p { margin: 0; }