I'm using Chrome on Android, and it the site doesn't seem to work correctly on mobile (maybe it isn't intended to- in that case, sorry!) The initial badge selection screen isn't cleared after one is selected, and by scrolling to the right, I can see a clutter of other elements underneath.

Thanks for pointing that out! We didn't check things out on mobile so we'll add a notice for mobile users in the short term and look at real support in the longer term.

iOS 11 and Safari here. Same thing for me. I can’t do anything with the site.

Seems to be the case with all the mobile browsers I checked with.

Fun to mess around with. I wasn't able to change the text size though. It was either 30 or, if I completely deleted the size, it seemed to default down to 14. On Firefox 59

Thanks mustoffa, I've replaced the numerical input with a slider, it should act more reliably now.