Sticky mobile menu

Hi there, I have had three sleepless nights trying to get the sticky mobile menu to work but to no avail.

I tried the following on additional css. It works on mobile but screwed up on desktop view:

#sidebar {
????background:#fff;
????height:60px;
????z-index:170;
????margin:0 auto;
????border-bottom:1px solid #dadada;
????width:100%;
????position:fixed;
????top:0;
????left:0;
????right:0;
????text-align: center;
}

Any help please? Thank you so much!

The page I need help with: [log in to see the link]