Hi – here’s what I see:

So I’d certainly agree there are a few CSS issues here, but it isn’t quite as you described (being outside the button boundaries etc) … I just wanted to check in the first instance if we actually are seeing the same and/or get a little more information if we’re each seeing something different, such as what browser you are using.
We can definitely do a few things to improve its visibility re the above screenshot, though (which is the result of CSS rules from your theme, best I can tell).
Let me know!