$default-variables: (
  "Card__Thumbnail__border-radius": var(--radius--med) var(--radius--med) 0 0
);

@mixin generate-toggle-theme-variables($theme-variables: ()) {
  $variables: map-merge($default-variables, $theme-variables);

  @each $name, $value in $variables {
    --#{$name}: #{$value};
  }
}