Colour Management with Sass Maps # ref: http://conormcafee.co.uk/journal/colour-management-with-sass-maps.html?utm_source=designernews

application.sass

a {
  colour: brand-colour(blue);
    
    &:hover {
      colour: brand-colour(blue, dark);
    }
}

brand_color.sass

$brand-colours: (
    grey: (
        base:   $grey,
        light:  lighten($grey, 10%),
        dark:   darken($grey, 10%)
    ),

    orange: (
        base:   $orange,
        light:  lighten($orange, 10%),
        dark:   darken($orange, 10%)
    ),

    blue: (
        base:   $blue,
        light:  lighten($blue, 10%),
        dark:   darken($blue, 10%)
    ),

    green: (
        base:   $green,
        light:  lighten($green, 10%),
        dark:   darken($green, 10%)
    ),
    
    white: (
	    base: $white
    ),
    
    black: (
	    base: $black
    )
);

@function brand-colour($brand-colour, $tone: 'base') {
    @return map-get(map-get($brand-colours, $brand-colour), $tone);
}

variables.sass

$grey: #C1CAD6;
$orange: #EF4640;
$blue: #4392F1;
$green: #00A676;
$white: #ffffff;
$black: #525252;