How can I maximize my logo size in the header?

This is my first post. I’m just starting to use Shopify, but I’ve spent a few years in WordPress, and before that Html/CSS. I’m a bit rusty, though, so I need some hand holding.
HERE’S my REQUEST:
I want my logo to fill up as much of the header as possible. Possibly even over flowing it. Where do control margins, padding, etc., for the header? Code please? Here’s what it looks like now:
https://releasethequackin.net

Thanks

Try adding this custom css:

.header__heading-logo {
height: 150%;
width: 150%;
margin-bottom: -80px;

margin-top: -51px;

}

Hi @Quackin

This is Richard from PageFly - Shopify Page Builder App, I’d like to suggest this idea:
Online Store ->Theme ->Edit code
Assets ->Base.css

.header__heading-logo {
    height: 150px !important;
    width: 555px !important;
}

Hope you find my answer helpful!
Best regards,
Richard | PageFly

Well, the logo is bigger. But it’s not centered. Also, it doesn’t fit on the Smartphone screen.

Got any other ideas?
Look at it on your smartphone.

http://releasethequackin.net

Thanks for your help!