On the page /index-test.html, I have augmented the CSS implementation of the color schemes with a JavaScript implementation. The CSS implementation works without JavaScript, but it requires the use of :has(), which earlier browsers do not support. The JavaScript implementation is working on both my Kindle browser and on both Chrome and Edge on my iPad 2, though the latter two require you to save your change before it takes effect. I don't think there are browsers more primitive than these that still need to be supported. By providing both a CSS and a JavaScript way to change the color scheme, this expands the number of browsers it will work well on. I plan to add the code for this to the site tomorrow. In the meantime, try it out and let me know how it works for you, particularly if you have some older device I am not using.
On the page /index-test.html, I have augmented the CSS implementation of the color schemes with a JavaScript implementation. The CSS implementation works without JavaScript, but it requires the use of :has(), which earlier browsers do not support. The JavaScript implementation is working on both my Kindle browser and on both Chrome and Edge on my iPad 2, though the latter two require you to save your change before it takes effect. I don't think there are browsers more primitive than these that still need to be supported. By providing both a CSS and a JavaScript way to change the color scheme, this expands the number of browsers it will work well on. I plan to add the code for this to the site tomorrow. In the meantime, try it out and let me know how it works for you, particularly if you have some older device I am not using.