Use the theme editor's Header section to enable full-width header, show header border, enable sticky header, and show logo image in sticky header.
Enable full-width header
This setting allows the header to span the full width of the browser window. This is most noticeable on larger screens, and may not be visible on smaller screens or devices.
Show header border
This setting will add a thin border between your header and the rest of your site content on all pages except the home page (you will have to navigate away from your home page in preview in order to see it).
Enable sticky header
Also known as a persistent or fixed header, this feature keeps the header within view as customers scroll down the page.
Show logo image in sticky header
This is a smaller version of your logo that will appear to the left of your navigation in your sticky header and provide a link back to the home page.