Checkerboard background pattern mixin

checkerboard.scss

@mixin checkerboard ($c1, $c2, $sx, $sy) {
  // Usage:
  // @include checkerboard(<color 1>, <color 2>, <cell width>, <cell height>);
  $sx2: ($sx * 2);
  $sy2: ($sy * 2);
  background: {
    color: $c1;
    image: linear-gradient(to bottom right, $c2 25%, transparent 25%, transparent 75%, $c2 75%, $c2),
      linear-gradient(to bottom right, $c2 25%, transparent 25%, transparent 75%, $c2 75%, $c2);
    position: 0 0, $sx $sy;
    size: $sx2 $sy2;
  }
}