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

Design policy: A single deep green on a white background. Almost no filled surfaces; hierarchy is built with lines, circles, and green text. As a corporate site for a household goods manufacturer, it balances cleanliness and calm - Density: Relaxed. Body text 16px, article line-height 2.0. Against a 1200px container width, the body column is narrowed to 677–900px - Keywords: Deep green, half-width punctuation, palt, circular buttons, white background