You're missing some semicolons. Assuming that's an exact copy-and-paste, some parsers will throw away min-width and height, some will throw away height, and some (ADE) will throw away the entire stylesheet.
After you fix those typos, if the problem doesn't go away, try using media queries:
Code:
@media amzn-mobi {
// Styles for older devices
}
@media not amzn-mobi {
// Styles for newer devices
}
and see A. whether it is using the mobi styles or the kf8 styles, and B. whether you can come up with a compromise that makes "Look Inside" behave without wrecking the formatting elsewhere.
BTW, I recommend running your CSS through CSS Lint, if you haven't already:
http://csslint.net
Not everything it whimpers about is necessarily a mistake, but it is good to look through them anyway.
