How to resize widgets so logo is centered on webpage

I'm new to having a website and I really want to put my logo at the top center of my page but the widget in the top center makes the logo really small.

The widget on the top right makes my logo big and I want that sized widget in the center so my logo will be big.

How do I go about doing that? I know I'll have to use the HTML editor but what do I input on the editor to switch the 2 widgets? I'm not HTML savvy.