I'm quite surprised the domain is "steamcommunity.com" and not "community.steam.com", it made me hesitant to enter login details.
% wc -l /etc/services
599 /etc/services Name Server: NS1.VALVESOFTWARE.COM
Name Server: NS2.VALVESOFTWARE.COM
Name Server: NS3.VALVESOFTWARE.COM
Seems legit.