This document discusses ways to customize the user interface in modern SharePoint sites. It explains that themes, site designs, hub sites, and formatting tools can be used to control aspects of the look and functionality. Various Microsoft tools and services are also presented to facilitate UI customization, including the SharePoint Design website, Provisioning Service, and Modernization Scanner. The recap emphasizes using themes, designs, and hub sites for branding and consistency across related sites while extending customizations through SharePoint Framework solutions.