Unavailable. Nobody can download this version any more, with elm or with the Lamdera compiler: github.com/rakutentech/r10 exists but has no tag 2.1.1; Software Heritage not asked yet (this run's --swh-calls were used up); no fork with tag 2.1.1 found (60 same-name repos checked); no cached copy. Use another version.
These lists are just to be used to create documentations, not to actually use colors in the layout.
Base colors are the only color, together with one primary color, that are used to derive all other colors for the interface.
They are different depending on the mode:

These represent the brands color of Rakuten.
Rakuten Brand guideline: https://global.rakuten.com/corp/brand/

These lists should only be used to generate documentation.
A sligtly modified version of Color.Accessibility.maximumContrast