Here are some key points about CSS:

• CSS is designed to enable the separation of content and presentation, including layout, colors, and fonts.
• It improves content accessibility, provides more flexibility and control in the specification of presentation characteristics, and enables multiple web pages to share formatting by specifying the relevant CSS in a separate .css file.
• CSS can be used for basic document text styling, creating layouts, and adding effects such as animation.
• The syntax of CSS is relatively simple, and it can save a lot of work by controlling the layout of multiple web pages at once.
• External stylesheets are stored in CSS files, which can be linked to multiple HTML pages, making it easier to maintain and update the styles.