New User - Interface Question

Brand new user...on first opening LibreCAD Im presented with a completely black background for the toolbars, menubars, status bar, etc. For the life of me I cannot see how to get this to change to the gray background I see on so many of the training videos. Do I have to edit the default style sheet? I've tried chaning the Application Preferences and the Widget options but I can't get there

I have this interface:



But would like this interface:



Thanks

The Page Preview under the File Menu is possibly what you are seeing in the Videos. You can only adjust the Page Layout in this view though.

A fellow Newby