.scroll-top-button {
  position: fixed;
  right: 20px;
  bottom: 36px;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 50%;
  background: #191a18;
  color: #6bd606;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: 0.3s;
  z-index: 1;
}

.scroll-top-button.visible {
  opacity: 1;
  visibility: visible;
}