The graphic charter is consistent throughout the digital book.
The graphic charter must make it possible to translate the structure of the work: the reader must be able to find their way in the progression of the plot, the hierarchy of information, etc.
Objectives
Allow homogeneity and continuity in reading and navigation.
Implementation
Use one or more style sheets that allow for a coherent layout of the text and/or different content.
Ensure that the fonts included in the digital book are readable by all audiences.
Control
The control takes place when checking the display of pages in different environments (i.e. reading software, e-readers).