.reading-progress {
  position: fixed;
  z-index: 2100;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  transform: scaleX(0);
  transform-origin: left center;
  background: #ad4c28;
  box-shadow: 0 1px 4px rgba(33, 26, 22, .22);
  pointer-events: none;
}

@media (prefers-reduced-motion: no-preference) {
  .reading-progress {
    transition: transform 90ms linear;
  }
}