body {
  height: 500vh;
  padding: 0;
}

.container {
  position: sticky;
  top: 0;
}

.main-content {
  position: relative;
  height: 90vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  text-align: center;
}

.home-sentence span {
  opacity: 0;
  transition: opacity 250ms;
}

.button-scrolldown {
  position: fixed;
  left: 50%;
  bottom: calc(var(--grid-gutter)/2);
  transform: translateX(-50%);
  transition: opacity .2s;
}

.button-scrolldown.hide {
  opacity: 0;
}

@media only screen and (max-width: 900px) {

  .main-content {
    height: auto;
    margin-top: 6rem;
  }

}