1. A method comprising: interfacing, by a graphics export subsystem, with a graphics design subsystem to access data representative of a graphical user interface screen design, the graphical user interface screen design including a building block placeholder element having an identifier associated with the building block placeholder element; detecting, by the graphics export subsystem, the building block placeholder element in the graphical user interface screen design; accessing, by the graphics export subsystem from a repository of building block elements, data representative of a building block element associated with the building block placeholder element by querying the repository of building block elements to identify, based on the identifier associated with the building block placeholder element and an identifier associated with the building block element, the building block element; generating, by the graphics export subsystem based on the graphical user interface screen design and the building block element, computing code configured to be processed by a target computing device to render a graphical user interface screen in accordance with the graphical user interface screen design and the building block element; accessing, by the graphics export subsystem from the repository of building block elements, data representative of an additional building block element associated with the building block placeholder element by querying the repository of building block elements to identify, based on the identifier associated with the building block placeholder element and an identifier associated with the additional building block element, the additional building block element; and generating, by the graphics export subsystem based on the graphical user interface screen design and the additional building block element, additional computing code configured to be processed by an additional target computing device to render an additional graphical user interface screen in accordance with the graphical user interface screen design and the additional building block element; wherein the building block element, the target computing device, and the graphical user interface screen are associated with a computing platform; and the additional building block element, the additional target computing device, and the additional graphical user interface screen are associated with a different computing platform.