[webkit-dev] Clear colour

Hi, I am creating a web site designed to be used by a Kiosk, in a dark environment. The problem I have is because I use frames page loading seems to bit slower and so the white colour that is used to clear the page before a redraw is very apparent. Since Safari does not allow me to change this colour, I am planning on making a custom build of WebKit. For this reason I would appreciate it if someone knows offhand which file I should be looking at to save me a bit of time. André-John