No space between navigation menu and post title in single post

Hi,

Please, how can I add some space between my site's navigation menu and post titles in single posts. As you can see on this screenshot https://prnt.sc/tnei9w, the title is too close to the navigation menu, can i shift the title down a bit, it's also affecting the sidebar. I will love to have a space between the menu and the title and sidebar too.

Secondary, how can I make my logo to be dack and also eliminate the big background? Here, https://prnt.sc/tnejhy, the logo is white, which is the primary logo I set for the site's homepage. And it also has a huge background.