.scroll-to-top-btn {
  position: fixed;
  right: 1.6rem;
  bottom: 1.6rem;
  z-index: var(--z-index-sticky);
  width: 4.4rem;
  height: 4.4rem;
  border-radius: 50%;
  border: none;
  background: rgb(var(--color-background));
  color: rgb(var(--color-text));
  box-shadow: 0 2px 8px rgba(var(--color-shadow), 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
}

.scroll-to-top-btn .icon {
  transform: rotate(-90deg);
}