Master layouts are important building blocks in the construction of your Wild Apricot site. Each website theme contains multiple master layouts, which define the basic layout of pages, and contain some of the graphical elements common to the theme.
For example, you may have three master layouts in your system – one with a sidebar, header and footer, another with a header and footer but no sidebar, and one for landing pages, with nothing except a single content area. Master layouts form the basis for page templates, in the same way that page templates form the basis for pages. 
Within a master layout – and consequently, within page templates – the areas in which content can be placed are defined by placeholders. Placeholders are specially defined areas that serve as containers into which gadgets and layouts can be dropped when editing a page template or page.
A plain master layout consists of a single placeholder. A master layout with the phrase mobile panel in its name will include a mobile menu panel when viewed on a mobile device.
Master layouts are not accessible through a graphical interface but can be modified through theme overrides. For instructions, see Customizing master layouts. You can also change the background colors and images used in master layouts from the Colors and styles screen. For more information, see Setting site backgrounds.
