I have recently redesigned my website. The new design has a light grey background for the main post matter. I matched the Adsense ad to the color and gave it the same background. However I have noticed that the CTR has dropped considerably with the new format.
Is it that Adsense works best with a white background? Or is the general rule even for websites - where white is the universal choice for background.
There isn't an answer that works for every site. It depends on your site, your niche, your users, how you blend the ads with your site, the size - all you can do is test various things to see what works best. And it doesn't even have to be consistent - on one of my sites, a 468x60 with a white background and blue or red text works best, while on the very same page, the 160x600 works better with a light blue background than a white one.