Two tonal steps of the working ground (#2F292A · #3D3536). Accounts are told apart by tone + the account word on the row, never by a hue. On the chrome a pebble is the raised-brand step; a .postie-working re-entry inside the chrome restores the working steps (context tokens, not descendant rules).
On paper the steps are #DAD8D8 · #C7C4C5 with charcoal ink (13.06 / 10.71). Inside the chrome the pebble is #282627; re-entered, it is paper-step again — the marketing cards and the paper-preview rely on this.