title: WYSIWYG Styles summary: Add custom CSS properties to the rich-text editor. # WYSIWYG Styles SilverStripe lets you customize the style of content in the CMS. This is done by setting up a CSS file called `editor.css` in either your theme or in your `mysite` folder. This is set through :::php HtmlEditorConfig::get('cms')->setOption('content_css', project() . '/css/editor.css'); Will load the `mysite/css/editor.css` file. Any CSS classes within this file will be automatically added to the `WYSIWYG` editors 'style' dropdown. For instance, to add the color 'red' as an option within the `WYSIWYG` add the following to the `editor.css` :::css .red { color: red; }