.back-to-top {
  position: fixed;
  bottom: calc(var(--space-6, 45px) + var(--back-to-top-footer-offset, 0px) + 10px);
  left: var(--space-6, 32px);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px Solid var(--color-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  /* transform: translateY(10px);
  transition: opacity .3s ease, transform .3s ease, visibility .3s; */
  z-index: 999;
} 

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
  stroke: var(--color-secondary);
}