I have the same issue, no way to fix it.
Just ensure that :
Let’s take an other view.
The action card has been changed, but this is basic HTML and basic styling. So don’t ask how to change it back, but deal with the new situation. In that case you can change the styling like Shekhar explained in his answer.
My advise: do not only know how to use, but also how it works under the hood.
hi Jingrui,
In style properties set margin,padding,height,width according to your requirement.
thank you