Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.3.14)
// Compass (v1.0.1)
// ----

// Color variables
$darkwing-duck-purple: #582e76;
$launchpad-red: #7e1a03;

// Placeholder selector for @extend
%button {
  border-radius: 3px;
  font-size: 13px;
}

// Mixin
@mixin button($background: blue) {
  @extend %button;

  background: $background;
  border-color: darken($background, 5%);
}

// Map that sets options
$buttons:(
  primary:(
    background: $darkwing-duck-purple,
  ),
  secondary:(
    background: $launchpad-red,
  )
);

// Loopy loop loop
@each $type in map-keys($buttons) {
    .button-#{$type} {
      $button-color: map-get(map-get($buttons, $type), background);

        @include button($button-color);
    }
}

SassMeister-output.css

.button-primary, .button-secondary {
  border-radius: 3px;
  font-size: 13px;
}

.button-primary {
  background: #582e76;
  border-color: #4a2764;
}

.button-secondary {
  background: #7e1a03;
  border-color: #651502;
}