In this demonstration you can interactively color the map of Europe using the IDP language. The text box allows you to write your own theory, and pressing Run generates a colored map of Europe which takes this theory into account. The buttons on the left provide you with three example scenarios.
You can use the following vocabularium:

Border(Country,Country)
Color(Country):Col

Colors and countries can be directly referred to using double quotes and lowercase. E.g.

Color("belgium")="red"