SVG web sites
You can use Inkscape to build simple and fast web sites.
Inkscape uses vector graphics and stores its content in text form. For example, if you save an image with a circle, it just stores the coordinates and colour of the circle. This makes for small files that the browser can just load directly, without the overhead of tools like wordpress, resulting in very fast pages.
To demonstrate or develop a site, just save the files as a .html in Inkscape on your desktop and open them in your browser. To turn this into a website, upload them to a shared hosting provider like Dreamhost and name your main page index.html.
This is an quick and dirty way to set up a site, but there is also very little to go wrong with it or require maintenance. If simple updates like new phone numbers or correction of links are ever required they are easy. You don't even need Inkscape, just edit the text file, find and edit what you need, and save the change.
If a web site already exists, Inkscape can still be used to add functionality. HTML5 can render the SVG content generated by Inkscape. Just open the .svg file saved in Inkscape, add a <svg>...</svg> tag to the existing page, and paste the content of the .SVG file into that tag.
See https://bearheating.ca for an example.