With the category custom field "Body class" you add one or more CSS classes to the HTML body of a category. This lets you apply individual CSS adjustments for one or more categories.
Separate several classes with spaces.
Example: special-category or special-category highlights
You can find the "Body class" custom field in the respective category:
Tab "General" ⇒ Block "Custom fields" ⇒ Tab (Set) "Categories (ThemeWare® ... Pro)"
Type: Text
Technical name: twt_{theme}_{edition}_custom_field__category__body_class