If we create the Feature image in each page/part, we could use it in the Table of contents for a more visual style.
Allowing a dynamic configurization:
- to have the feature image in all the pages,
- to have the feature image in all the parts,
- to have the feature image in all the pages and parts,
- Not to have the feature image at all.
Now is pretty symple. I attach the place for the feature images in the TOC.
Imagine to change the title of the Part: Main Body for a picture.
Of course the picture have to have the proportions between 1:6 - 1:9.
