Off-white background (#F7F7F8). Barely gray, just enough to make pure white surface cards pop. That technique gives every card a defined, elevated quality without needing shadows. The text (#131316) is near black with a very slight purple undertone that ties to the accent. The muted text (#5E5F6E) is cool gray-purple. Even the secondary content reinforces the violet palette.

Inter at weight 700 with aggressive -0.03em letter-spacing on headings. This is tighter than most systems. The heavy weight plus tight tracking combination reads as precise and authoritative. Authentication infrastructure needs to feel serious. Body text at weight 400 with 1.5 line height keeps compact information dense and readable. The heading line height at 1.1 compresses those bold letters into tight, powerful blocks.

At 14px base size with compact density, this is a system for dashboards and documentation. Not leisure reading. 0.75em paragraph spacing keeps information tight. The typography is functional: it conveys structure and hierarchy instantly. JetBrains Mono for code blocks is critical here because a lot of what Keystone-styled products show is code, API keys, and webhook payloads.

Surface definition shadows. 1px 3px at 6% opacity plus a 0 0 0 1px ring at 4% opacity. This is the technique that gives Keystone components their defined, card-like quality without dramatic shadow. The 1px ring acts as a permanent subtle focus state at rest. Darken hover effects create precise interactive feedback. Fast motion speed means everything responds instantly. Ring focus style with the purple accent makes interactive states clear and accessible. The large shadow at 25px 50px is reserved for modals. On everyday surfaces, borders and rings do the depth work. Precision is the atmosphere.