Why are the buttons twitching on hover?

Question

css

the page needs to be scrolled a little down kodirovanie-alkogolizma.ru

Answer 1

.btn:hover {
font-weight: bold;
border: 0 !important;
font-size: 14px !important;
padding: 8px !important; // !!!this should be removed!!!
}
main.css : 453

Answer 2

hover is written crookedly
on hover changes the size down
while hover naturally flies
well and in a circle
it is much more reasonable if you really need to reduce the size
to reduce the contents of the block without changing the block itself

Answer 3

Because :hover reduces padding.