using images in the css of a theme/postdata on a single line

Im making a custom theme, and its all going well, EXCEPT for two things…I cannot seem to EVER be able to use images in the css, such as background images for the DIVS that are holding the elements of the theme such as the header, or the sidebar etc…also, for every post, Im trying to get the meta data of the post to all sit on a single line, instead of being on two lines like:

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also, I am testing this theme locally, I have installed wp locally on my machine to test, could that be the reason that when previewing the page in firefox, none of the images in the css show up. The only image that shows up is one that is directly inserted into the php file using a full URL, after hosting the image on my server.

sorry if all thats a bit confusing, but its driving me mad!

thankyou! ??