When reading the documentation website, I'm finding that unless I have the browser window fully maximised, the content is formatted in the narrow layout.
The content should flow on the right-hand-side of the menu.
The menu is the full width of the window and the content flows below the menu.
Any width below 1200px causes the content to be placed below the full width menu. This 2/3 the width of my laptop screen.
I would suggest making this smaller and consistent with the main project page (http://flink.apache.org/) which has the breakpoint set to about 840px.