Group avatar on mobile --> css bug

Hi..

the group avatar css setting is not very well because on mobile the image dont scale down and is out of center ..
here is the line:
body div#fd.es .es-avatar.es-avatar-large img {
height: 172px;
width: 172px;
}

it should be like this:

body div#fd.es .es-avatar.es-avatar-large img {
height: 100%;
width: auto;
}