Hello and thank you for the kind words.
The simplest way to prevent the auto responsiveness of an image is via CSS. Edit the custom.scss file and add the following rule:
.gantry-logo img {
max-width: inherit;
}
This will force the logo to always fit its natural size. Of course you can also decide to have it forced at a minimum size. For instance if you want the logo to always be at least 100px, you could say:
.gantry-logo img {
min-width: 100px;
}