BlocksCAD is an Open Source, Web based CAD programming tool. It’s underlying syntax is based on OpenSCAD.
You can find details about BlocksCAD at thier website: https://www.blockscad3d.com/
Try out the tool on their website as well:
https://www.blockscad3d.com/editor/
The Render seems to be done with JSCad, which enables the web based approach.
This is a great tool and advanced designs can be accomplished quickly.