You can take a look at live examples here: https://datamaps.world/projects/europe-housing-price-statistics.
Besides publishing interactive maps, you can export them to high-resolution PNG or SVG.
Nice work -- I do research in data visualization and may be writing a formal paper soon. This is a personal research question since I see this used in a lot of maps -- what do you say is the the advantage of a discrete stepwise color scale vs a continuous gradient when expressing indiscrete linear data? I want to be able to say the pros and cons for each as I write a quick guide for mapmakers who don't have a design background to make better color-choices in their maps.
There is no right or wrong when choosing a data classification method. It's all about telling a story, so you just to have play with color scales and see what feels better. When you use a continuous scale and your data are not equally distributed (there are some outliers), you will get almost every country shaded with the same color except that outliers.
This is an interesting guide about data classification on maps: https://www.axismaps.com/guide/data/data-classification/
I would love to take a look at your guide when it's finished.