Effects for page sections (section is a top level row in the page builder) can be set in the page builder row settings inside X40 Effects section. Effects for nested rows are not supported. Effects are displayed in the nested rows settings, because page builder does not allow to disable settings only for nested rows, but they are not supported by the theme. A text notice about this is displayed under the input fields.
Effects for common elements like footer and comments and for default page layout can be set via page builder also, via
Appearance / Widgets in the WordPress Administration Panel. See Default Layounts, Default Layounts, Comments. This backgrounds can be overrided in the page settings on page editor bottom. The options
Override Default Content Backgrounds,
Override Footer Backgrounds,
Override Comments Backgrounds for this purpose.
Most effects are given by a number. The range of allowed values is indicated in parentheses after the effect name.