The brief was make it legible at night. We almost obeyed. Pure white on pure black is a screen test, not a register. We followed the brief halfway. The half we kept is what makes the page readable after forty minutes; the half we discarded is what would have made it readable for four.
Why pure white fails.
At a contrast ratio of 21:1, white type on black ground produces a halation around each letterform — the light spills, the edges feather, and the eye fatigues faster than it would on a sheet of newsprint under a desk lamp. The figure is not theoretical. We proofed Edition II at #ffffff. Returning readers told us the type vibrated. They did not use the word halation. They used the word headache.
The fix is not contrast reduction. The fix is the right white. We moved from #ffffff to a paper-warm cream — #ece9df— and the vibration stopped. The ratio dropped to 17.4:1, which still clears every accessibility floor and still reads as bright on the matte ground. The page stopped vibrating. The reader stopped flinching.
Black wants company. White is too eager. The right white is the one that arrives a step behind.
The dim accent.
The accent palette — used for chapter numerals, the corrigenda mark, the cursor, and the cart total — is set at #c7c4b7. Dimmer than the body, dimmer than the chrome, dim enough that the reader registers it as a second voice and not as a duplicate of the first. Two whites on a black ground sound, at first, like a mistake. They are not. They are the difference between a page that speaks and a page that announces.
Display type — chapter openers, the volume title, the running folio — is set in the body white. The accent white is reserved for marginalia and metadata. We have never run display in the accent. We have never run a folio in the body white. The two whites do not cross.
A note on the cursor.
The custom cursor on the editorial chrome is the accent white at40% opacity, with a hairline ring at the body white. The configuration is deliberate: the cursor is a second presence on the page, not a third. If it were the body white it would compete with the type; if it were the accent it would disappear against the marginalia. The compromise is the only honest choice the layout allows.