S2:Theme Layer

One set of these layers are supplied by LiveJournal's servers and override properties and may redefine functions to give you examples of what the layout can do. They most oftenly have different color schemes that you can choose from.

When not using a server-supplied theme layer, you can create your own and use it to override values of properties that are defined in the Core Layer or defined and/or declared as used in the Layout Layer as well as redefining functions. You will need to use a theme layer to keep the custom values of properties that are defined in the Core Layer but not declared as used in the Layout Layer.