I need help with css editor

* Check the “Advanced user” option.
* Go to Styles – Styles manager.
* Create a new Style.
* Go to the Page tag – “Contents area background” block.
* Select a background image.
* Click on Finish.

Is that what you need?

If you want it only for the old Free text iDevice, you can use this CSS code (paste it in the Advanced tab of the Style Designer, in the content.css block):

.iDevice_wrapper.FreeTextIdevice{background:url(yourImage.png) repeat 0 0}

I hope it helps.