One scale, three weights, two text colours, and the rules that keep every component consistent.
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const ready = trueBody text and controls sit on text-sm; everything else is a step or two from it. Large titles tighten their tracking a little, body text keeps the font's own.
Labels say what happens, with one capital at the start.
Two text colours, foreground and muted. Colour is kept for status and the one primary action.
No eyebrow label above a heading; the heading already names the section.
Interface copy uses full stops and commas. No em dashes.