Thank you so much for using our theme. I think that you want to add the logo size bigger ? If so, try once by adding the bigger logo size image. If no any changes will arise, you have to write some custom CSS code for it.
You can add custom code here: https://doc.acmethemes.com/acmeblog/#WhereandhowtoaddcustomCSS
If you feel any problem, please feel free to ask.