<model-viewer> v3.0 is here! This includes two major new features: Dynamic Hotspots and Animated Textures. See all the bug fixes, editor improvements, etc in our release notes:

Dynamic hotspots let you connect your DOM to the 3D model, even as it animates, and it all keeps working in #AR with #WebXR too. Use our editor to easily select hotspot locations:

You can now create textures from #video, #canvas2D, and even #Lottie animations and apply them to your model: This is especially good for electronics where you want to display activity on its screen.

The breaking change causing our major version bump is that we no longer support the deprecated @glTF3D Specular Glossiness extension. However, our editor now losslessly auto-converts Spec-Gloss models to Metal-Rough:

We've also pushed out a v3.0.1 with a number of bug fixes and examples updates for cross-browser compatibility:

I've searched looking for the answer to this but there is no way to change the background colour which defaults to white without adjusting the styles.css within the zipped folder once downloaded. Is this correct?

Yes, the whole point of our downloadable starter-website is to be configured further to your needs.