frappe/webnotes/public/css/avatar.css

.avatar {
	display: inline-block; 
	vertical-align: middle;
	border-radius: 50%;
	overflow: hidden;
	background-color: #ddd;
	border: 1px solid #eee;
}

.avatar img {
	width: 100%;
	height: auto;
}

.avatar-small {
	margin-right: 5px;
	width: 30px;
	height: 30px;
}

.avatar-large {
	margin-right: 10px;
	width: 72px;
	height: 72px;
}