@function color($key) {
    @return map-get($colors, $key);
}

@function color_lighten($key, $amount) {
    @return lighten(map-get($colors, $key), $amount);
}

@function color_darken($key, $amount) {
    @return darken(map-get($colors, $key), $amount);
}

@function to_opacity($color, $opacity) {
  @return rgba(color($color), $opacity);
}