The
offical FAQ mentions that this thread is the right place to contribute to the official FAQ.
The answer to the following FAQ question: How do I add margins to the text? could be significantly improved.
In particular, body { margin-left: 2em; margin-right: 2em; } is recommended, which will only add left and right margins. Extending this example to body { margin: 2em } doesn't work well either, adding top and bottom margins only to the entire book.
After a fair bit of searching on this forum, I discovered that a better approach for margins is: @page { margin: 2em; } which will add margins to every page of the book.