Use the document theme classes of OfficeThemes.css to specify fonts and colors that match the theme of the presentation your content add-in is inserted into - and those fonts and colors will dynamically update if a user changes or customizes the presentation's theme. Using OfficeThemes.css, design add-ins that are coordinated with PowerPoint in two ways. PowerPoint assigns a new blank presentation with the default Office Theme, but you can choose other themes available on the Design tab, download additional themes from, or create and customize your own theme. To apply or customize the theme of a presentation in PowerPoint, you use the Themes and Variants groups on Design tab of the ribbon. An Office theme consists, in part, of a visually coordinated set of fonts and colors that you can apply to presentations, documents, worksheets, and emails.
