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

Design approach: A clean system-font configuration that leads with Helvetica Neue for Latin text and falls back to Hiragino Kaku Gothic ProN for Japanese. A three-layer setup that also uses Open Sans weight 600 for navigation labels and Noto Sans JP for some headings such as lens descriptions - Density: Body text 15-16px / line-height 1.6 / letter-spacing normal. Compact typesetting that balances product grids with readability - Keywords: Zoff Blue #4998db, pill buttons, clean white-based EC, Open Sans navigation, Latin-first font stack - Characteristics: - Page background is pure white #fffff