The same word-mark as your homepage, with black text instead of white so it's legible on light backgrounds (Google result cards, YouTube channel banner, business card, letterhead). Red icon, red Z, and red BOOKKEEP are preserved.
PNG exports have a transparent background — drop on any color.
For a YouTube channel banner, use the 2048px size. For a business card, use 1024px or the SVG.
For a social share / OG image, use the 1024px size.