I am trying to make some modifications to Bartik starting with a background image for the header. I have followed some instructions to create a sub-theme and this seems to have worked. My sub-theme is called mybartik.
I tried making some changes to my sites/all/themes/mybartik/css/colors.css which don't seem to be followed. I have found a directory called sites/default/files/color/mybartik.407xxxxx which seems to be a replica of my sub-theme files at a certain point in time. If I make changes to the colors.css file in that directory the website reflects the changes instantly.
I am trying to find out the correct place to make my changes, and if it is to the files in the .407xxx directory, will they be permanent. If the changes should be made in my sub-theme directory, which seems like the right place, how do I get them recognised by the system.
Thanks and regards