Increase Desktop Logo Size

Site URL: https://www.mirboonorthwinterfest.com.au/

I am trying to increase the desktop logo size to about 450/500px (currently 320px in the design section, and I can't go any higher). 

I am using this code but nothing is happening, what am I doing wrong? 

/* increase logo size */
.header-title-logo img {
    max-height: 450px;
}

You'll need to increase the max width like this in the Custom CSS:

.Header-branding-logo {
    max-width: 450px;
}

Awesome, thanks so much!