bitFlyer Style Design System (DESIGN.md, Japanese UI)

Design policy: Designed to make numbers readable. On top of a bluish white (#fdfdff / #f5f8fd), monospaced-digit tickers and rounded cards are arranged. A single highly saturated blue is concentrated on CTAs - Density: Extremely high. The visible text on the top page spans 759 elements (of which about 350 are price tickers). Letter spacing is left completely untouched, and line height is tightened to 1.00 - Keywords: tnum, Nunito digits, weight 600 as default, bluish white, blue & orange