#ace {
width: 50vw;
height: 50vw;
background: green;
transform: skewY(-45deg) rotateX(30deg);
}
#bace {
width: 50%;
height: 50%;
background: black;
transform: skewY(45deg) rotateX(-30deg);
}
<div id="ace"
>
<div id="bace"
>
</div>
</div>
Even with the opposite transformations applied, I'm still unable to revert it back to its original state.