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

Design policy: Builds a natural, plant-derived brand worldview around two colors: Deep Green #004727 and Sunflower Yellow #fed14a. Combines D2C modernity with pill-shaped CTAs, palt headings, and Montserrat English labels - Density: Heading line-height 1.4, body 2.0 — generous line spacing. Large photography and a layout rich in whitespace - Keywords: natural green, sunflower yellow, pill CTA, palt headings, D2C, plant-based - Characteristics: - The brand color is Deep Green #004727 (CSS variable --color-green). Used for the header, heading color, and footer background - The CTA accent is Sunf