You can modify and customize the layout of chapters, sections and pages for iBooks. iBooks are better designed if chapters, sections and pages follow a certain predefined layout so that once the iBook finished, changes such as background color, line spacing, etc, can automatically be made to all chapters, sections and pages as desired.
You can have access to an iBook layout as follows:
1 - click on the pop-up view menu
2 - select "Show Layouts" and "Show Layout Boudaries" as shown in the picture below.
The layout pane is shown on the left (red arrow). If you scroll down the layout pane, you can select chapter, section and page layouts and modify them as you wish.
There is more on modifying layouts chapters, sections and pages in any template
More Free Tutorials on iBooks