Hi,

If you would like to use a different background for the WYSIWYG editor. In such case, you need to specify the CSS styles like these:

.LTR, .RTL
{
// set the dark background here
background-color: black;
}

BODY
{
// do not set any background here ...
}

The LTR/RTL style is used only for the web page background, while the BODY style is used for both the page and the WYSIWYG editor. Alternatively, you can create a separate CSS stylesheet and assign it to the editor in CMS Site Manager -> Sites -> Site Properties -> General dialog - Editor CSS stylesheet

Best regards,
Ivana Tomanickova