OnlineBrief24 Letter

A modern DIN 5008 business letter built on onlinebrief24 (calibrated against the onlinebrief24.de hybrid-mail service). Ships with the class's `guides` overlay ON, showing the real DIN 5008 zone geometry, fold marks and address-window boundaries directly on the page — a technical inspection mode most users will turn off, kept on here so the geometry is visible in the preview.