Is there any way to change font size of Quantity Gift widget?

Also, how do I set up the widget that will cap each class's enrollment? and is there any way to change font size?

It seems that this is related to thread 1944324. Please refer to that thread regarding the "capping".

You can adjust the font size of this widget by injecting a custom CSS code to the widget itself. Here's the code you can use. Just set the size to your preference.

#checklist{

font-size:10px;

}

Please refer to this quick guide on how it's done: