As a web developer: your site is clean and crisp, with an almost brutal simplicity which makes it very attractive. Honestly, I like it a lot. It could use one or two very subtle tweaks in the super-fine details, but for a technical information-dissemination site, it’s bloody awesome.
My only issue is with the width. While whitespace between the sides and the centre content is very useful, this isn’t the 1990s anymore with its 1024×768 monitors. You _can_ make the centre column responsive to the overall width of the screen. Doing so can also give you a lot more room to do things, and make it easier to read. Your line-height is already great, and is perfect for text blocks a good half again wider if not twice as wide. Even on my vertical monitors, which are only 1500px wide, that centre column is pretty much claustrophobically narrow.
One piece of good news is that you just need to drop #page-wrapper's width (or adjust to preference) the rest of the CSS all appears to be sensibly responsive.
My only issue is with the width. While whitespace between the sides and the centre content is very useful, this isn’t the 1990s anymore with its 1024×768 monitors. You _can_ make the centre column responsive to the overall width of the screen. Doing so can also give you a lot more room to do things, and make it easier to read. Your line-height is already great, and is perfect for text blocks a good half again wider if not twice as wide. Even on my vertical monitors, which are only 1500px wide, that centre column is pretty much claustrophobically narrow.