Compatibility

it should work on the following screen sizes (these are the sizes and browsers the rest of the app is being tested on):

• 4.7 inch phone (iPhone)
• 5.5+ inch phones (general android phones)
• 10 inch tablet (iPad, say)
• 14+ inch laptops

and must have browser compatibility for

• Firefox (Desktop)
• Chrome (Desktop)
• Edge (Desktop)
• Chrome (Android)
• Safari (iOS)
• IE 11 (best effort)

In general, you shouldn't have issues with JS compatibilty unless you're using some funky ES7 which you might need to polyfill, but CSS behavior can differ seriously between desktop browsers (which are somewhat consistent), Chrome for Android and iOS Safari.

Also, you could take cues from the rest of the app if you're unsure how this is supposed to look in responsive mode. In general, the screen is divided into three parts for desktop and tablet, with the navmenu at the left, a list or editing area at center and detailed information to the right. There are reusable components to make such a layout. More specifically, check the feed, calendar, add-event and update-body components' layouts.