If I'm not mistaken, the background of the header is colored, but height is determined by the size of the font and elements in there. If I increase the font, the size of the header increases, but I think the other elements in there control it as well. You could probably reference it by the div id and set an absolute height for it.
For the side bar, I'm guessing you mean in spaces where the side bar exists. For that element:
Hope that helps!
Hi team, I’m Avinoam, a product manager on Confluence Cloud, and today I’m really excited to let the Community know that all customers can now try out the new editing experience and see some of the ...
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