Can themes style the visual editor? « Andrew Ozz on WordPress
http://azaozz.wordpress.com/2010/01/02/can-themes-style-the-visual-editor/
Can themes style the visual editor? Short answer: yes. This has been available for quite some time but don’t think I’ve seen themes that do it. Things like typefaces, headings, image padding and borders, etc. can easily be set by the current theme making the visual editor… more WYSIWYG. All it takes is a stylesheet and a small function in the theme’s functions.php file: