allow changing theme on narrow screens

[nstringham]

Problem

users with screens narrower than 480px cannot change the theme or pack

Work around

most users with narrow screens have the ability to make their screens wider through window resizing or device orientation change

Suggested solution

add an overflow menu on narrow screens to hold the theme pack and about icons

Alternatives solution

you could also just get rid of the search bar on narrow screens and require users to go to index to search for a user

Additional context

originally brought up by potted plant on discord here

[nstringham]

this could also be solved by adding a settings menu and putting themes and pack in the settings menu