Thanks dgatwood,
I tried that last night. I opened an AZW3 version of my book and a mobi version, on the Kindle Fire 7HD. There's a big difference... the headers look HUGE on the fire HD, when in AZW3, but the mobi version looks fine/nice. The words look closer together on the AZW3, which gives it more of a book feel... BUT, there are lines throughout my whole book, in that every so often are stretched, so there is white spacing. It's distracting, and breaks the flow. Although I'm told there's nothing I can do about it
Other than hyphens, but I can't seem to get hyphens to turn on!! I've set them to 'auto' in the css, but nothing. Yet the headers hyphenate (against my instructions), so my Kindle obviously supports hyphenation.
This coding is so complex!
I think I'll post another thread on this, and see if anyone can help me to figure out how to turn hyphens on, and to decide whether to go with the AZW3 file or the mobi one. I can't decide!