Just upgraded the theme; Header image size is “small”

After updating the theme (from version 1.2.6 to 1.2.7), the size of the header is to “small” (I can see less then the half of the image). It occurs only while I’m using a screen resolution width more then 1365px.

I guess that the problem is in the style.css, but I can’t fix it.
— in style.css —
@media .site-header
{
min-height: 120px;
}

—

I if choose a smaller resolution, everything is fine:
@media (max-width: 1365px) and (min-width: 1280px)
.site-header {
height: 320px;
}