Carrier graphic top left, slanted REALLY under it on every page. Mobile: burger opens a full drawer with Sign in and Contact. Desktop: the same two as text links. Has a footer.
Logo in the shared bar, step progress under it on mobile and inline on desktop. No menu, no footer, so nothing pulls people out of the flow.
Signed in. Desktop: no top bar, logo heads the side rail. Mobile: shared bar with logo and burger. Privacy and Terms sit at the bottom of the rail; Support replaces Contact. No footer.
--shell-h 64 / 88 desktop, --shell-pad 20 / 40, --shell-max 1200), mark left-aligned and vertically centered, so switching shells never moves it · 22px logo · same burger (44px hit, 26px icon) and full-width drawer · black-fill active nav item. Signed in users open Terms and Privacy inside the App shell. Contact is public only; signed in, it goes to Support.