Remove Space Between Site-Title and Main Navigation Menu

Hello, I hope you're well. We are not using the Site-Description area in our header. Hence, I want to remove the space it's taking up as it's giving me a big area of whitespace between the site-title and the main navigation menu. However, I tried to use custom CSS to reduce the space by using #site-description then reducing the border, padding, etc. and it has had no effect. So my question is how to do you remove the whitespace between the site-title and the main navigation menu in the header?