Redesign wins: flat surfaces. Sheet v3 lighting (gradients, lit edges, soft shadows) is retired.

Elevation and material

One dark world of flat tones. Things are separated by a step in tone, never by an outline or a shadow. The only depth is the solid floor under a button cap, which the cap sinks onto when pressed.

--color-bg · ground (edge drawn here only to show it)
--material-low = sunken · rows, cards, slots, chips
--material-raised = surface · quiet buttons, tree tiles, selected row
--material-raised-hover · hover of a surface, idle dot
--elevation-selected · 4px mint bar inside the bottom
--elevation-cap-primary · --size-floor 5px mint-deep floor
--elevation-cap-take · coin-deep floor
--elevation-dialog · kept from sheet v3 (redesign has no dialog)