Tsuchiya Kaban Style Design System (DESIGN.md, Japanese UI)

Design policy: A brand site composed of "DM Sans + DNP Shuei Gothic Gin + weight 300 + wide letter-spacing," conveying the quiet pride of leather artisans. A Latin-first font stack that places DM Sans (geometric sans-serif) at the front for Latin text and combines DNP Shuei Gothic Gin (Adobe Font) for Japanese text. Headings use a separate serif stack of Adobe Caslon Pro + DNP Shuei Mincho, forming a dual-typeface system. The entire site is unified at weight 300 (ultralight), with a pure white #ffffff background accented by a deep navy blue #004b87 - Density: Relaxed EC style. Large product ph