Abstract: One exemplary embodiment involves receiving a request at a server device, the request identifying electronic content and a modification for the electronic content. The request may be based at least in part on information provided in a uniform resource locator (URL) or other address used by a requesting client device to initiate the request for the electronic content from the server. A parameter of the URL or other address may be used to specify the modification. The exemplary embodiment further involves identifying, via the server device, a source file associated with the electronic content, changing, via the server device, an element within the source file according to the modification identified in the request, and providing modified electronic content from the server device for use on the requesting client device.