Pressbooks allows you to customize your theme's CSS. 

This means that if you know a little CSS, you're not limited to the default styles in the 20+ themes provided by Pressbooks. You can modify ours, or build your own. 

To customize your CSS: 

1. Go to Appearance > Custom Styles from the left-hand menu of your book's dashboard

2. Select the style sheet you'd like to edit – there are three CSS files to customize for the three different export types (Web, ebook, print book), and you must edit them separately. Use the dropdown menu to select which CSS file you would like to edit

3. Enter your CSS customizations in the Your Styles box 

4. Click Save when you've made your changes

Here are a few of the elements you can customize in the CSS for the PDF or print version of your book: 

Half-Title Page

Running Heads & Running Feet / Footers

Left or Right Chapter Openings 

Custom Page Size or Custom Trim Size

Font Size and Line Height 

Margins 

For more advanced troubleshooting for CSS customization, email support@pressbooks.com