First of all, the layout is pretty nice, the only problem for me is how dark it is. The dark font on the dark grey-green coloured background can be a little bit hard for me to read if I have the backlight on my laptop turned down (at night for example). It just seems like a bad colour contrast.
I'd maybe try a lighter colour like the grey in the hearder, and just use the green as more of a background accent type thing. But you'll know what looks best for you.
That's all I can think about at the moment.