reducing size of language switcher

I am trying to reduce the size of my language switcher.  It seems to be defaulted to the body font size but I would like to to be the same size and family as my menu but cannot work out  how to identify its class.  I would like    font-size:16px;    font-family : 'Arial', sans-serif;

 

Sorry - it is the login/logout I am having difficulty with. I have given the login button a class of login-button and in my custom css I have
.sclogin .logout-link .login-button{
font-size:16px;
font-family : 'Arial', sans-serif;
}
but they don't take effect.