[MARCO1]

Originally Posted by Vaira

At ACP choose Style manager (at the style to be modified--->edit templates-->double click on CSS Templates, double click on additional.css and add to change background color from grey e.g. to color #d3ddf3:

.cke_skin_kama .cke_wrapper {
    background-color: #d3ddf3 !important;
}

To use e.g. border color #acacff, border 1px solid and padding 0px:

span.cke_skin_kama {
        border: 1px solid #acacff !important;
        padding: 0px !important;
}

To change the background color of the text box from white to #333333 :

.cke_skin_kama textarea.cke_source {
        background-color: #333333 !important;
}

Use your desired color / padding / thickness of the border.

No need to edit the original css'es. These changes will remain at every update then, since the original css'es are untouched.

Enjoy!

Greets Vaira.

I'll add this as a new feature for my upcoming version, You should be able to do that from my modification admincp settings