The principle of devolution states that all powers are devolved to the Scottish parliament in Holyrood unless they were specified in the list of reserved powers as set out in the 1999 Devolution Act.
This is a six page leaflet has a lot of information about the details of that principle including changes made after the 2014 referendum. It answers questions like “Why doesn’t the Scottish government do more about poverty, etc…” And it has information about the extent of Scotland’s natural resources. it doesn’t cover the recent Brexit raid on devolved powers.
If you need a high resolution file use this link: Powers Devolved to Scotland. These images are good enough to load to websites or share to social media.