html,
body {
  --visibleHeight:100dvh; /*calc(var(--vh, 1vh) * 100);*/
  overflow: hidden;
  user-select: none;
}

.frames{
  height: var(--visibleHeight);
  overflow-x: hide;
  overflow-y: auto;
  scroll-snap-type: y mandatory;
}
.frames > .frame{
  scroll-snap-align: start;
  background-repeat:no-repeat;
  overflow:hidden;
}