:root{ --scale: 1; }
html,body{ height:100%; margin:0; background:#2b2b2b; overflow:hidden; }

/* host */
#frame-wrap{
  position:fixed;
  inset:0;
  display:flex;
  align-items:center;     /* centro */
  justify-content:center; /* centro */
  overflow:hidden;
}

#p6-frame{
  display:block;
  width:1920px;
  height:1080px;
  transform-origin:center center;
  transform:scale(var(--scale));
  border:0;
  background:#fff;
  flex:0 0 auto;
  max-width:none;
}