Themes stopped working (+ solution)

The reason why other themes stopped working is commit a1c32b63fb43de0b5bb44fe16f53006e6e07be7f which gives the default style (white background, black text color) more importance than theme styles because it has been moved into form#dw__editform.
My solution is to move all theme styles into form#dw__editform so they can override the default style again.