I ride by the Envelope Architecture and Design office on 6th street every day on my way to ILE.
It is on a nice shady street, with awful pavement, but a variety of buildings. Some victorian houses, some commercial concrete structures, and some residential. But the building that catches my eye is Envelope A+D. Structurally, it is nothing special, but I love the way it is styled. Dark and light grey on perpendicular faces, with cyan doors.
Incidentally, It is an aesthetic that is carried through all of the firm's projects.
We brought these colors directly into a collection of backpacks--