 In this video we will provide an introduction on using Custom Styles in Pressbooks. Custom Styles is where you can customize the CSS for your book theme in Pressbooks. To access Custom Styles, expand the options under the Appearance tab in the Dashboard menu and click Custom Styles. The Webbook, eBooks, and PDFs each have their own Custom Styles sheet, which allows you to customize the CSS depending on the export type. This means you should always check to make sure you are editing the correct Style sheet, and if you want to change Apply to each format you will have to add the CSS to each Style sheet. In this video we will focus on the Web Styles. There are two text boxes. The first is called Theme Web Styles, which contains the CSS for the theme that you are using. This cannot be edited, however you can scroll through the CSS and you can search. To search, click anywhere in the text box and click Control or Command F. This will cause a search bar to pop up. The second text box called Your Web Styles is where you can add your own CSS to override the CSS that appears in the Theme Web Styles. One thing to note is that the CSS that Pressbooks uses is finicky and you will need to match it in order to have your changes reflected. As such, I recommend searching for the thing you want to change in the Theme Web Styles box. Copy it into Your Web Styles and edit it there. For example, if you wanted to change how block quotes appear, you could search for block quote. Copy the entire entry and paste it into your Web Styles box so you can edit it. Once you've made your changes, you can click Save and they will be reflected in the format that you are editing. And that's how to edit the CSS of your book theme in Pressbooks. Thank you for watching.