Not bad, but I think there’s one big way that you could improve them: do a lot more of the styling on the _a_ tag. At the moment, you are only able to click on the text, because most of the button belongs to the li tag, which doesn’t react to clicking.
I’ve put together what I generally do for buttons [here](http://codepen.io/David_Leitch/pen/lmAws “Button examples”) to give you some suggestions. I’ve used a bit of Sass to put mine together, which you don’t need to use, but I just find it makes them a lot quicker.
Nothing wrong with them but they are actually list items rather than a `
However, as usual, you still have a lot of repeated CSS in there.
Firstly, if all of your link list items are going to be the same EXCEPT for the background color then you can combine those properties into a class and leave the individual coloring to a separate class.