I just ported this site to Drupal 8. I used the built-in migration for D7 to D8 and it worked fine. I also created a D8 theme using JQMobile for this site. One of the features is an option for modal pages (any page that has 'modal' in its url). The code for this is at https://github.com/karens/jqmobile.
Update: I'm now trying out a different theme, based on Bootstrap, so the jQuery mobile effects won't work any more.