This works better for me:

  # Productivity
  127.0.0.1       mail.google.com
  127.0.0.1       gmail.com
  127.0.0.1       news.ycombinator.com
  127.0.0.1       www.bbc.co.uk
  127.0.0.1       netflix.com
  127.0.0.1       www.youtube.com
  127.0.0.1       arstechnica.com
  127.0.0.1       theverge.com
  127.0.0.1       www.google.com
  127.0.0.1       xkcd.com
  127.0.0.1       duckduckgo.com
  127.0.0.1       www.theguardian.com
  127.0.0.1       www.apple.com
  127.0.0.1       store.apple.com
  127.0.0.1       www.microsoft.com