Wider Alert Window on Tablet

I have an alert where a user must select from a list of radio buttons, but some of the names run off the edge of the page. This is understandable on a narrow device like a phone, but our app is aimed at tablets and we’d like to take advantage of the wider display.

Is there a way to forcefully apply CSS to the Alert window such that it will be “width: 360px; max-width: 90%”? I’ve tried modifying “global.scss”, but that didn’t do anything.