What accent colors should I use for browns?

[Bria]

I just moved in my new apartment, so I'm very new to decorating. I just bought a sectional, and it's a couple different browns. It's a dark brown leather at the bottom/back with light brown almost like a sand color cushions, and dark, medium, and light pillows. I was thinking about keeping it warm and earthy. I was thinking maybe a dark green? What are your opinions? I also need ideas for curtains. Thanks in advance. :)

[pollo]

Blue is my opinion because blue is cool and warm color, try this.

[loanstoreuk]

I think blue will be awesome.