:root{
  color-scheme: dark;
  background:#000;
}
*{box-sizing:border-box}
html,body{
  margin:0;
  width:100%;
  height:100%;
  overflow:hidden;
  background:#000;
}
body{
  min-height:100vh;
  min-height:100dvh;
}
#viewerFrame{
  display:block;
  width:100vw;
  height:100vh;
  height:100dvh;
  border:0;
  background:#000;
}