How can the appearance of a Liferay site be customized?

Customizing the appearance of a Liferay site typically involves working with themes, layouts, and style books. Themes in Liferay allow developers to change the overall look and feel by providing a way to customize the CSS, JavaScript, and images that define the site's presentation. Layouts determine how content is organized on the pages, allowing for flexibility in design. Style books enable the application of consistent styling across various elements of the site without needing to manually adjust every single component, streamlining the customization process.

The other options, while they may involve legitimate actions within Liferay, do not directly address the primary methods for customizing appearance. Altering core server configurations is more related to site functionality rather than aesthetics. Relying solely on third-party plugins can limit customization to what those plugins offer and may not fully utilize Liferay's built-in capabilities for appearance adjustments. Editing HTML files in the backend can be risky and is not the standard method for customization since it bypasses Liferay's structured theming system, which is designed for managing site presentation in a more organized and maintainable way.