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

Design policy: A restrained modern editorial style, built on a pure white background with deep navy #001646 (midnight blue) as the brand color, typeset in Helvetica + Yu Gothic Pr6n (Adobe Fonts) - Density: A grid densely packed with large product photos. Information is pared down to a minimum, with product visuals as the star. Low information density, high photo density - Keywords: pure white background, deep navy accent, Helvetica + Yu Gothic Pr6n, letter-spacing wide, palt, tight headings at line-height 1.0, rectangular 48px line CTA, zero border radius, YakuHanJP punctuation handling - Cha