I want to add logo to my navigation bar ,how can i change background of logo according to background of my navbar?
I’m not sure if I completely understood your problem, but I can say that generally you need a logo with a format that supports transparency (JEPG does not support it but PNG does). then you should make sure that it has a transparent background and if not make it’s background transparent with a photo editing software. after that, if you place the image anywhere on the page, you will see what you expect.
If you are asking about PNG images, those are transparent and the logo will look great over the navbar color.
If you have jpg image, then that logo is not transparent. So say you have a logo in a rectangle and you want the area outside of the logo to match the navbar you will probably have to use photoshop to change the color of it.