Adicionar .css ao ckeditor
config.contentsCss = '/css/mysitestyles.css';
config.contentsCss = [ '/css/mysitestyles.css', '/css/anotherfile.css' ];
Hurt Hamerkop
config.contentsCss = '/css/mysitestyles.css';
config.contentsCss = [ '/css/mysitestyles.css', '/css/anotherfile.css' ];