Flexible design architecture for designing media-based projects in a network-based platform

Methods and systems of inter-relating themes via a design and a layout relationship are disclosed, offering flexibility in design and data relationships of media-based projects. In one embodiment, an Internet user at a user-device selects a theme from a plurality of available themes, the theme being a collection of designsets. The system automatically selects a design from the designsets that best fits the content provided by the user. The design automatically inherits a layout from a layoutset corresponding to the automatically selected design. The design defines style and formatting over the layout, while the layout defines the locations of photos and text. When a user selects a different theme, the system can quickly adjust the design without input from the user, increasing user friendliness and usability. The user can create additional personal customizations, and print the final design to create a photobook or other media-based project.