Developing a WebApp

Are you trying to control the lights from the Argon, or bypass it and control the lights directly because they are "smart"?
If you go through the Argon, then you can use HTML code to generate a POST request.
IOW, you still need to give someone either a file or an app to make HTTP transactions.
This documentation should help: Cloud API reference | Reference Documentation | Particle

If you decide to go with an app, the simplest one I can think of is this: Simple App to call a particle function - #10 by Pescatore
Or search upward in that thread.

More details would help with suggesting solutions.