For a solid light-map background #f7f5ef, calculate the WCAG relative-luminance contrast ratios, rounded to two decimals, for source teal #205d71, submitted red #8c331f, and Run violet #5f438c. Report named values source_contrast, submit_contrast, run_contrast. These numbers test this solid swatch only; an imagery basemap needs its own inspection.
A worldwide GIS learning platform needs one map language across its catalogue, results and Run previews. A source airport, an unsubmitted result and a submitted result must remain distinguishable; the same rules must work in light and dark themes. The world source includes country boundaries, rivers and airports. The team must also prevent a partitioned Morocco from appearing in either data or pre-rendered tiles.
Deliver a design system in three handoffs: quantify contrast on a specified solid background, decide the semantic portrayal and data rules, then create a versioned registry for style tokens and layer rules. Treat the supplied geographic files as data on a real projection. Contrast on one swatch does not certify an imagery basemap; inspect each real background. The design system is for worldwide maps, not a regional visual brand.
These are where the teaching is. Read them twice.
The OGC Symbology Conceptual Core Model treats styles as reusable portrayal rules (https://www.ogc.org/standards/symbology-conceptual-core-model/). The MapLibre style specification defines layer order, sources and paint/layout properties (https://maplibre.org/maplibre-style-spec/). WCAG guidance says meaningful graphical cues need appropriate contrast and colour cannot be the only carrier of information (https://www.w3.org/WAI/WCAG22/Understanding/non-text-contrast.html; https://www.w3.org/WAI/WCAG22/Understanding/use-of-color.html).
Work the problem in whatever tool you like, then enter the answers here.
source_contrastsubmit_contrastrun_contrast3 scored, 0 informational
Source swatch contrast
33%Submit swatch contrast
33%Run swatch contrast
33%