Sydney Theme: How to make Logo and Menu side by side in Header?

Hello,

I am a newbie, actually a first time user of WordPress (Sydney Theme, free) and I made this website (https://cms.computer-m.de/) for just 2 (two days).

Not getting into details:
I need help in the Header area.
I would like to move the MAIN MENU closer/next to the logo (which is set on the left) in order to increase the font size and have it just in one line (not in tablet or phone mode though).
I would also maybe change the MAIN MENU font in ALL CAPS.
And it could also be bold.
(would like to see how it looks to decide if I should use it or not)

Thank you in advance for the help.
(FYI: been searching this topic for 2 or 3 days now, all I found didn’t help)

The page I need help with: [log in to see the link]