Hi there,
this CSS is controlling the width of the site logo on desktop and mobile:
.site-logo {
max-width:140px;
}
The mobile header uses the menu item height to size the logo and to keep it vertically centred, its the two together are causing the problem.
Try adding this:
#mobile-header>.inside-navigation {
align-items: center;
}
.mobile-header-navigation .mobile-header-logo img {
height: auto;
padding: 0 !important;
}
I removed the padding as well to make it a little larger.