Main menu above centered logo

Dear support team,

First of all, thanks for the many updates. I really appreciate the time spent to continually improve the Enfold theme.

For approximately a year now, I am using your theme. In a child theme I worked with a style.css file for customization, as I wanted a centered logo and an always fixed to the top main menu, without a header secondary menu, social icons and phone number. Together with some tweaks in the header.php file, my custom css worked perfect together with the plugin UberMenu (to get a 100% full width). Until the recent major update.

With the new header option ‘Logo center, menu below’ selected as well as custom css in my child theme in the file style.css I am able to get the same effect as described above, only much easier. The problem I am facing, though, is that in Chrome the fixed to the top main menu is sometimes frozen in the middel of the screen (or somewhere else, but not fixed at the top) after a few times of scrolling. It seems to me, that my custom css is conflicting with your code, and at your forum I cannot find the right solution. Therefore, my following question: can you please advise me, which custom css to use to properly position the main menu above the centered logo and always fixed to the top. Nb. the logo should not stay fixed at the top like the main menu and I would like to keep it the same size.

The custom css I am using:

#header_main_alternate { 
	background-color: #4d4d4d !important; 
	position: fixed !important;
	margin-top: -151px !important;
	width: 100%;
	z-index: 500;
	height: 40px !important;
	border-bottom: hidden !important;
	border-top: hidden !important;
}
.av-main-nav > li > a { 
	color: #f8f8f8 !important; 
}
.html_header_top #top .av_header_stretch .container {
    width: 100%;
}

@media only screen and (min-width: 990px) {
  /* Add your Desktop Styles here */

.logo img {
  margin-top:57px !important;
  max-height: 80px !important;
}

Besides this css, I am also using custom css to style the UberMenu. And for the mobile views I also have some custom css to center the logo in a right way and to adjust the margins.

I am looking forward to hear from you, thank you in advance!

Best regards, Fleur