Here we are dealing with this site's navigation, so the 'demo' is the actual nav that you are using to get from page to page here. It is important that the element with the ID 'myNav' keeps its ID, as it is being used in the java script to make the whole thing work. Also the names of the open and close buttons must not be changed. The width of the navigation can be changed, though. If you want to change it, it has to be done in the 'script' section at the bottom of the page. It is at 250px now, and it may be set to e.g. 100vw if you want the navigation to cover the whole page width. Both pixels, percent and viewport width (vw) can be used.
Download the component.