A portal visual identity is made of HTML produced as a result of portal aggregation (the components that make a page like columns and rows combined with the content produced by the portlets) and associated CSS files.

EPP allows to deploy multiple skins consisting of CSS files, which makes it possible to apply styling to the page compositions and components of a page (portlets). Different skins can be applied to the different websites, also if made available to the users, they can choose their preferred skin.