Thanks for your information.
I did a little experiment using an excellent illustrated EPUB that has been published here (
Claudio Bombarnac) and I made a comparison with the integrated style activated or not (screenshot 1 and 2).
It seems that the Koreader software takes correctly into account the following CSS:
width:80% for the top image and
width: 5em for the lower one when using the integrated style while the display of the non integrated style stays very poor.
The image sizes are 310×438 for the top one and 400×157 for the lower one (small train).
I will try to use
width instead of
max-width which seems to be unsupported. I know also that the property
float is unsupported.