How to change the border of a button, its thickness?

Answer 1

none,dotted,dashed,double,groove,ridge,inset,outset and hidden are the other border-style values

for more informations:-
https://www.w3schools.com/css/css_border.asp

Answer 2

border: 5px solid black;

that 5px can be changed to get proper thickness.

Answer 3

thanks @Elizabeth

Answer 4

thanks @Niush

Answer 5

there is any other style than solid??

Answer 6

other than solid there is dotted and double