Two claims, made checkable

The 404's chromatic tear carries two assertions in its comments that nothing on the page proves: that mix-blend-mode was the wrong tool, and that the periods have to be non-harmonic. Each of these builds the rejected version so the claim can be checked in a click rather than believed.

Both alternatives fail slowly. Give each a full minute — the blend one needs a theme toggle to show its problem, and the harmonic one needs two full cycles before the repeat becomes obvious.