As circled in the diagram above, the width changes from 0.38 to 0.25 as we go down the ramp (or at least, that's how I interpreted the diagram). How can I go about doing this—as far as I know, extrude only extrudes in uniform length. Furthermore, what confuses me is how would I know where exactly on the ramp it begins to be "0.25" rather than "0.38" or any other number. Any help would really be appreciated.