Sealious Playground generates its colors dynamically in https://hub.sealcode.org/source/sealious-playground/browse/master/src/back/colors.ts.

They then are available as CSS variables and can be previewed in localhost:8080/dist/colors.html.

Each color then has about 10 shades of it generated, with -0 being the darkest, and -9 being the brightest:

The task is about adding a boolean toggle called dark_mode in the color generating script. If set to true, the order of shades should be reversed — -0 being the brightest, and -9 being the darkest. This will let developers use the colors more semantically — "closer to 0" will mean "closer in brightness to text color" and "closer in to 9" will mean "closer in brightness to canvas color"