Hey, I have no idea about the colours to use for adsense, I wanted to know what is working best for people that have done testing. Been using it years so I really should have done some testing by now! My current sites are all on travel and the sites are all light green headers and forum backgrounds are light green. Thanks!
If your forum background is light green it is better to set adsense background also to the same color. Remove adsense borders. Let the ads being shown as part of your content of the website. When someone read the ads try to focus them towards the header. Making the headers darker is a good practice. Use light colors such as light grey for url links. Avoid unnatural bright colors at all cost. Remember ad placement is also important as the appearance of ads.
Most people do use colors similar to their blog as the header of the ad. But sometime a vibrant color also does a job and produces better ctr. As who knows people coming to a particular blog like vibrant colors more than dull colors.
here I recommend to use bright colors, but is more advisable to use the same color with the color of the website.