CSS
Z MoodleDocs
CSS or Cascading Style Sheets are used to control the way web pages look. CSS files are located in the theme folder being used by Moodle. The normal Moodle practice is to have 3 main CSS files: styles_color, styles_layout, styles_fonts. When a CSS defination is not found in a theme CSS file, the CSS files located in the standard theme serve as the default. There may also be CSS files for Internet Explorer, Mozilla or other internet browsers.