JPG and web colors Colors

Hopefully this isn't a dupe post, but here goes. I'm out of ideas for this problem I have. I want an image which will merge with a flat background color, let's say dark blue (#003366), and want it saved as a JPG. If I save the image, which is, say, a photo of me with the background set to #003366 and the background in my HTML page is set exactly the same, then the background on the image is noticeably lighter than the HTML document when viewed onscreen together.

In other words, I want the color on the background of the JPG image to match exactly the background of the HTML page. But I don't want the banding and large file size associated with a GIF. I have tried this on Mac and PC and they both do the same. And, yes, I could use a GIF but in order to make a photo look good enough, the GIF has to be 128bit dithered and the file size of the image would be too large then. Any thoughts?

You could always change the bg color to the same as what the jpg is on the dk blue part (when i tried it it was 003466) and say screw the people that don't use high color or better...

When you save as a .jpg the comression screws with the background color. No easy way around that :(

Yeah, that's what I figured. I find it strange though that JPG compression would actually change the value of colors. Suck. Back to the old GIF, I guess.