If you have long pages of content on the website sometimes it becomes painful for your website visitors as they have to scroll up and down to access navigation menu, in these cases a sticky menu which sticks in your header as you scroll down is very useful.
And it is possible to enable sticky menu in Directory theme by adding just a line of CSS code.
Please go to wp-admin >> Appearance >> Custom CSS Editor >> and here you can place the CSS code given below.
CSS Code:
.primary_menu_wrapper {background: #0165BD; position: fixed; z-index: 999999;width: 100%;}
After placing this code, please update the file. Clear your cache and browsing history and take a look at your site. Your primary menu should not be working as a sticky menu.