message: Use functional variables in documentation for BorderBox
diff: title: BorderBox
  ---
  -
  BorderBox is a Box component with a border. When no `borderColor` is present, the component defaults to a gray border.
  ## Default example
  @@ -20,9 +19,9 @@ BorderBox components get `COMMON`, `LAYOUT`, `BORDER`, and `FLEX` system props.
  ## Component props
  | Prop name | Type | Default | Description |
  -| :- | :- | :-: | :- |
  +| :----------- | :--------------- | :---------------------------: | :------------------------------------------------------------ |
  | borderWidth | String | '1px' | Sets the border, use theme values or provide your own. |
  | borderStyle | String | 'solid' | Sets the border style, use theme values or provide your own. |
  -| borderColor | String | 'gray.2' (from theme) | Sets the border color, use theme values or provide your own. |
  +| borderColor | String | 'border.primary' (from theme) | Sets the border color, use theme values or provide your own. |
  | borderRadius | String or Number | 2 (from theme) | Sets the border radius, use theme values or provide your own. |
  | boxShadow | String | | Sets box shadow, use theme values or provide your own. |
  