Forgot to mention that I have tried to limit the width of the HTML block by limiting the whole html, aka:

html {
max-width:1320px;
margin:auto; (to center it)
padding-right:0px;
padding-left:0px;

This made the HTML block 1320px but because the header is sticky it remains full width when the dropdown appears during a sticky header. Also, it puts additional paddings on the rest of the content and shrinks ia additionally, so I removed it.