There is a bug in the CSS for logo handling. I will get this fixed in the upcoming update this week. Meanwhile, you can use the following CSS to get the issues for you fixed (pls modify values based on your logo height and width) –
#header-logo, #site-title a { width: 220px; height: 150px; }
@media only screen and (max-width: 479px) {
#header-logo, #site-title a { width: 150px !important; height: 150px; background-size: 150px !important;} /* Reduce size for smartphones only */
}
If you still have issues, pls email me a temporary login to your site through my ThemeForest profile page. Will help resolve things much quicker. Thanks