How can I adjust the logo size on Dawn Theme header without altering its height?

[tysonmoss]

habing troubles increasing the size of my shopify header center logo it appears to be capped off at 

a certain height and width and cuts it off to fit that size. also i want to achieve 

this by keeping the header the same height, i figured out how to change the logo size by increasing the overall header but that is not ideal . 

dawn 13.0.1

https://636d88-f7.myshopify.com/products/escape-island-t-shirt