Increase Header Size

I am sure there is a really easy way to do this but I can’t find it (first time making a website). I was hoping to increase the size of my logo in the header just on the front page over the slider. Once scrolling, I don’t mind the size of the header but just on the initial page I would like them bigger.

Thank you in advance, love the theme!

Edit: Site is

Hi Clush,
this code below can help you to have maximal size of your logo, you can use custom css plugin to put this code:

.site-logo { 
  height: 100%;