.header-content {
  height: 100vh;
  height: 100dvh;
  background-color:#fff;
  color: #000;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  display: block;
  width: 100%;
  -webkit-transform: translateY(-100%);
  transform: translateY(-100%);
  transition: all 0.3s ease-in-out;
}

.menu-is-open .header-content {
  -webkit-transform: translateY(0);
  transform: translateY(0);
  -webkit-transition: -webkit-transform 0.5s cubic-bezier(0.215, 0.61, 0.355, 1);
  transition: -webkit-transform 0.5s cubic-bezier(0.215, 0.61, 0.355, 1);
  transition: transform 1s cubic-bezier(0.215, 0.61, 0.355, 1);
  transition: transform 1s cubic-bezier(0.215, 0.61, 0.355, 1), -webkit-transform 1s cubic-bezier(0.215, 0.61, 0.355, 1);
  overflow-y: auto;
}