> The higher a surface’s elevation (raising it closer to an implied light source), the lighter that surface becomes. That lightness is expressed through the application of a semi-transparent white overlay. This is a strange choice, considering that the guide has a very strong discouragement against emulating shadows…
> In a dark theme, components retain the same default elevation levels and shadows as components in lighter themes
It looks pretty good in the examples they give IMO. Considering that the default makes such heavy use of elevation it makes sense to keep that concept in the UI.
> Default themes use shadows to express elevation, while a dark theme also expresses elevation by adjusting the surface