/* Only the switch is styled here; it stays readable over the page with the reset on or off. */
.switch {
  position: fixed;
  /* Wide unstyled fixtures expand the layout viewport; viewport units keep the switch on screen. */
  inset-block-start: calc(100dvh - 1rem);
  inset-inline-start: calc(100vw - 1rem);
  z-index: 1;
  padding: 0.5rem 0.75rem;
  color: CanvasText;
  background: Canvas;
  border: 1px solid;
  translate: -100% -100%;
}