Added Custom Background Color to Effect>Style for a flexible control over the background color in the 3D viewport.
This feature meets the request of custom background color in specific projects, such as rendering composition materials or parallel projection views.
Notes:
Parameter priority: This setting will be overridden by the background color set in the Outline mode. Disable the Outline mode to restore the custom background color.
This parameter only affects the viewport background and does not change models, environment lighting, or reflections.
