// Grayscale
@each $key, $value in map-deep-get($filter, 'grayscale') {
  .u-grayscale#{capitalize($key)} {
    filter: grayscale($value);
  }

  .hover\:u-grayscale#{capitalize($key)}:hover {
    @media (hover: hover) {
      filter: grayscale($value);
    }
  }
}