On colours
On colours are colour roles for content placed on an associated surface, such as on-primary for content displayed on primary. The name expresses a relationship between roles
What it means, how it is used and where it comes up, with its related concepts.
What it is and how it works
This convention helps maintain consistent pairs but does not guarantee contrast. Actual values, opacity, text size and component states need to be evaluated. Changing a surface colour also requires reviewing the content displayed on it, including alternative themes and disabled states.
Also known as
On colors