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I didn’t even look if the position relative had anything to do with it. The major problem was that you had a specificity collision in your nav. Some elements were given specificity of header id and some navigation id. So if you want to keep your nav inside the header you do as I did. If you don’t want to have your nav inside the header then you craft your nav elements with specificity of navigation id and put it below the header with header having some bottom margin. Hope it makes sense.