My initial goal: to get a cover image to function the same visually (for epub3) in a web browser, + same as in a desktop epub, + same as in an Android eReader epub -- all to function like an SVG, but using just JPG/PNG image and CSS so the bottom of the image would not spread off page.
Having gotten that, next...we made the suggested code changes to get the cover image sit on the left panel of a two-page spread (horizontal mode).
Code:
#container img {
display: block;
height: auto;
max-height: 100vh;
max-width: 100vw;
margin: auto;
border: 0;
position: static;
column-span: none;
column-fill: auto;
}
Would this CSS change resolve BookFusion (on iOS) as well?