Notice: Moodle Docs will be switched to read-only mode starting on Tuesday 17 October 14:00 UTC for server maintenance. The estimated read-only period should not take more than 24 hours.
CSS or Cascading Style Sheets are used to control the way web pages look. By changing a CSS definition, the change is made on every Moodle webpage that uses that definition.
CSS files are located in the theme folder being used by Moodle.