Inverse Blocks CSS

_blocks-base.scss

.button--inverse .wp-block-button__link {

     @each $name, $color in $colors {

          &.has-#{$name}-color,
          &.has-#{$name}-color {
               color: $color;

               &:hover,
               &:focus {
                    color: $white;
               }
          }

          &.has-#{$name}-background-color,
          &.has-#{$name}-background-color {
               background-color: transparent !important; // need important to override gutenberg inline styles
               border: 2px solid $color;

               &:hover,
               &:focus {
                    background-color: $color;
                    border: 2px solid $color;
               }
          }
     }
}