You don't adjust the style of your frame directly, instead you only specify a type:
How the frame is going to look is adjustable via the preferences program.
Four spacing values belong to each frame that tell MUI how many pixels should be left free between the frame and its contents. These spacing values are also user adjustable as long as you don't override them with one of Area.InnerLeft, Area.InnerRight, Area.InnerTop, or Area.InnerBottom.
Note: The first object in a window may *not* have a frame. If you need this you will have to create a dummy group with just one child.