hanzo.io/public/css/hero.css

.hero {
  background-size: cover;
  background-position: center;
  height: 100vh;
  width: 100vw;
  min-height: 800px;
  box-sizing: border-box;
  padding-bottom: 50px;
}

.hero .summary-down {
  display: block;
  margin: 0 auto;
  position: absolute;
  bottom: 10px;
  left: 0;
  right: 0;
  width: 50px;
  height: 50px;
  border-radius: 25px;
  text-decoration: none;
  padding: 0;
}

.hero .summary-down:after {
  content: '';
  transform: rotate(45deg);
  display: block;
  position: relative;
  top: 15px;
  left: 17px;
  z-index: 101;
  width: 14px;
  height: 14px;
  border-bottom: 2px solid #000;
  border-right: 2px solid #000;
}

.hero .summary-down:hover:after {
  animation: 2s ease 0s bob;
  animation-iteration-count: infinite;
}

.hero .call-to-action {
  margin-top: 10px;
}

@keyframes bob {
  0%,
  50%,
  100%
  {
      top:15px;
   }

   25% {
      top: 13px;
   }

   75% {
      top: 17px;
   }
}