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

Design approach: A fintech site characterized by a large-area hero in Kyash Blue #2ad1ff (cyan-leaning blue) and proportional typesetting using Hiragino Kaku Gothic + palt. It combines a sense of cleanliness, transparency, and trustworthiness. - Density: A relaxed composition with generous whitespace per section. Emphasis on readability with line-height 1.9 (body text 14px → 26.6px) and very wide line spacing. - Keywords: Kyash Blue (cyan), Hiragino Kaku Gothic palt, fintech trustworthiness, card UI, near-white #fdfdfd background - Characteristics: - The brand color is #2ad1ff (Kyash Blue). De