Works fine with chrome/Android, the problem is with your HN reader. I had seen it bork few sites rendering in the past.
According to these stats [2], Android Browser has about 55x the usage of Chrome Mobile as of April 2013. This means ~97% of Android devices will likely show up as they do in my screenshot.
In short, the problem is not with my HN reader, the problem is with this CSS library on the most common Android browser.
[1] http://developer.android.com/reference/android/webkit/WebVie...
I am using SG-S3 for what its worth.
Most likely the whole css wasn't loaded completely. Could you retry couple of times to see if it happens again?