A design system taken from the notebook nearly every Japanese student has carried since 1975. The page is pure white paper. Pale blue rules sit on a strict 6 mm pitch, and one cornflower band runs down the spine carrying the Campus wordmark.

Everything else is held back. Fields are ruled lines with no boxes around them, and labels read like a printed spec: B / 6 mm / 30 lines. Each tint stands for a real rule width, and the dotted ticks set into each line mark column positions. It suits calm, structured interfaces that want to feel useful.