Use the color selector available in your adsense account or use php code with the javascript code to swtich colors.
Do you mean dynamically change background colors, well you can do it through PHP and Javascript. Anyway, you can set the adsense colors via the Adsense SETUP section. Is it allowed to change the adsense code?
just create two ads and have different colours for each, put the code for one at at the top and the other at the bottom.
You not supposed to but in the Adsense code is color codes. You can change these at your own risk. Like everyone else said, you can just change then in your account and then change the code.
i meen adsnse Appears in different colors when i do refresh to the page is it is in this forums in The upper part