The headers that push a bit into the margin are an interesting stylistic choice, but why on earth does it have to be random? Did something change that affected the layout somehow? (ironically)

It's different for the different header levels.

https://www.w3.org/Provider/Style/GuideStyle.css

    H1 { margin-left: -20%; }
    H2 { margin-left: -15%; }
    H3 { margin-left: -10%; }
    H4 { margin-left: -05%; }

I find it works well for helping maintain context. I often can't easily tell the difference between different headers unless they're right next to each other, and even then some of them are difficult to discern. Adding the indentation is a way to make the hierarchy more clear.