Signal Path token sheet, Rubric override. Proof surface for the design system (Design Loop step 3). The accent is vermilion, hue 40, from rubrication: the red-ink margin annotation that is marginalia. Every value here resolves to a semantic token in src/styles/theme.css.
The O-ring seals in the solid rocket boosters were not designed to accommodate the low temperatures1 present at launch, and the resulting loss of sealing capability was the direct physical cause of the failure.