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

Design approach: A clean product site based on white. The WHILL Blue #0075b8 pill CTA prompts action, while product photography and whitespace convey the sense of freedom of "free movement" - Density: Body text uses line-height 1.4–1.5 and letter-spacing 0.016em–0.02em, a moderate setting. Headings are tight (line-height 1.0–1.1), forcefully presenting product names. A generous, spacious layout - Keywords: Clean, product-focused, modern healthcare, openness, universal - Characteristics: - Monochrome brand: The main color is #0075b8 (WHILL Blue) only. CTAs, links, and secondary borders are all