Colours are defined in a multidimensional map, with base, light & dark variants.
Set colors with the palette() helper function in Sass.

primary
light
secondary
light
success
light
warning
light
danger
light
info
light
primary
base
secondary
base
success
base
warning
base
danger
base
info
base
primary
dark
secondary
dark
success
dark
warning
dark
danger
dark
info
dark

Example Code:

<!-- Set element to primary color bg -->
.element-primary {
    background: palette(primary);
}

<!-- Set element to primary light color bg -->
.element-primary-light {
    background: palette(primary, light);
}