Design a high-fidelity desktop web UI mockup, 16:10, rendered as a flat screenshot -- no browser chrome, no laptop frame, no hands, no desk, no perspective.

Brand: Subnaut. A developer tool. Tone: precise, quiet, engineered. Not playful, no gradients, no glow, no 3D, no stock-photo people, no purple-blue SaaS look.

Palette, used exactly:
  background   #ffffff
  raised panel #fbfbfa
  primary text #0a0a0a
  body text    #46464a
  muted text   #8a8a90
  hairline     #e8e8e6
  accent       #12a37a  (a restrained green -- use sparingly, for one action only)

Type: a clean grotesque sans (Inter/Helvetica feel) for prose. A monospace face for labels, eyebrows, code and buttons -- uppercase, wide letter-spacing, small.

Layout: generous whitespace, a strict 12-column grid, thin 1px hairline rules as the main separator instead of borders or shadows. Left-aligned. Flat.

Mood reference: the Bittensor site, Linear's docs, Stripe's density -- engineering documentation, not a marketing splash.

Page: a signed-in account home. Single centred column, about 640px wide, left-aligned.

Header row: a large display name, the email beneath it in muted grey, and an outlined "Sign out" button pushed to the right.

Beneath: a row of three flat stat tiles with hairline borders -- PLAN / Free, DEVICES / 3, MEMBER SINCE / Sep 2026. Uppercase monospace labels above larger values.

Then a hairline rule and a section headed CONNECTED DEVICES in small uppercase monospace: three rows, each with a device name in bold, a muted second line reading "connected 3d ago - last used 2h ago", and a small outlined "Disconnect" button at the right. Rows separated by hairlines, no fills.

Below, a quiet accent-coloured text link: "Connect another device".

Restrained and administrative -- closer to a settings page than a dashboard.

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If the result is wrong, reply with one of these:
  Use the accent on exactly one element. Everything else is black, grey and white.
  Remove all gradients, shadows, rounded cards and illustrations. Flat, hairline rules only.
  Double the whitespace. Reduce to half the elements.

Dark theme: background #0a0a0a, raised #131313, primary text #f4f4f5, muted #9b9ba3, hairline #26262b, accent #4fc69a.
Mobile: render at 9:16, single column, hamburger in the top bar.
