Here is a free resource that I wish I had found years ago: https://practical-svg.chriscoyier.net.

It underpins all I have harped on about the benefits of vectors for the majority of simple web imaging, an area that Xara is only just about touching in its latest versions.
The one I hate is Xara's use of turning a button text and its shape into two images, images that are repeated across all the pages of a NavBar without using an image filename to compensate for the repetition. These should be CSS as a minimum with the hope or using SVG animations too.

Many of Chris's examples can be ported into a Xara design.
If you have any ideas you want to explore, sing out.

Acorn