.scroll-down-arrow 
{
  left: 50%;
  bottom: 6%;
  width: 24px;
  height: 24px;
  position: relative;
  animation: scroll 1.5s infinite;
}

.scroll-down-arrow span 
{
  position: absolute;
  top: 50%;
  left: 50%;
  width: 12px;
  height: 12px;
  border-left: 2px solid black;
  border-bottom: 2px solid black;
  transform: translate(-50%, -50%) rotate(-45deg);
}

.scroll-down-arrow span:nth-child(2) 
{
  top: calc(50% + 6px);
}

.scroll-down-arrow span:nth-child(3)
{
  top: calc(50% + 12px);
}

@keyframes scroll 
{
  0% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: translateY(20px);
  }
}