Mixin to include with any fixed position styles to adjust for the WordPress admin bar.

wp-admin-bump.scss

// Use wherever a fixed position is declared to adjust for that pesky WP admin bar.
@mixin wp-admin-bump{
  .admin-bar & {
      margin-top: 46px;

      @media screen and (min-width: 782px){
        margin-top: 32px;
      }
    }
}