round button uses full width on mobile

Hello,

a round button.. (width 45px and height 45px) appears as long button on mobile phone.

height 45px is ok, but it uses the full width of div

within a div of 200px width the button has 45 px height and 200 px width

website is under construction and htpasswd protected, so I cannot send a link

I use the newest version 8.2 , if I upload version 7.8, it works fine

Thanks for your help