I would like to make an onclick button which slides in another page link and changes the URL that covers up 80% of the website, while the previous page stays in the background. When close, the URL returns to the previous one.
I thought of ways to achieve that, but none of them changes the URL of the page, such as
Like this site, page slides in when clicked and changes the URL
https://area17.com/work
You can achieve this by any of the methods you specified above by adding the following Javascript code for changing the URL without reloading the page.
window.history.pushState(state, pageTitle, theUrl);
https://developer.mozilla.org/en-US/docs/Web/API/History/pushState