Originally Posted by rwhe
My workaround was to download the MOBI version and convert it to EPUB with Calibre (you should have access to several different formats when you buy an O'R book).
It's also possible to convert the ePub to ePub. It's what I usually do when I bought a book from O'Reilly.
I think the CSS is too convoluted or something (doesn't really look better afterwards, if you ask me, though).