Take DPI into consideration before collapsing content below sidebar
On a Nexus 7 the content is shown beneath the list of feeds when held in portrait mode despite a horizontal resolution of 800px.
On a desktop with a regular monitor, no collapsing occurs when resizing the browser window to 800px wide.
I am assuming this is due to chrome reporting a lower horizontal resolution to your css media queries due to the higher display density. I have observed that your stylesheets already take dpi into account for your logo, so I am merely suggesting that you do the same for your layout.
On a side note, it's great that you provide a larger logo for higher pixel ratios (at and above 1.5), but that still leaves a minority of us (those with a pixel ratio of 1.3, which might be limited to the Nexus 7 for now: http://bjango.com/articles/min-device-pixel-ratio/) with a blurry logo.