Shared control packs

Control packs reduce repeated right-panel schema without hiding visible design.

For example, theme/controls/shared/box.json can define width, spacing, background and border controls once. A section references it inside its schema:

{
  "$ref": "shared/box",
  "overrides": {
    "width": { "default": "page" }
  }
}

An override may change a label, description, default, range, options or visibility. It cannot change the setting ID or type. Unknown packs, unknown override IDs and reference cycles fail validation.

Use a control pack only for a recognizable repeated group. Do not create one for two unrelated fields merely because their JSON looks similar.

Control packs create Founder Mode controls; they render nothing by themselves. The section or block still owns the HTML and CSS that use the resulting values.