First figure jumps when viewport width transitions between 1407 and 1408px

[laughinghan]

The very first figure, captioned:

Chrome browser displaying ‘This webpage is not available’ message

Jumps when the browser window transitions from 1407px to 1408px wide. From 1408px to about ~1430px wide, the right margin of the figure is too small or nonexistent:

As the window is resized, pay attention to how the margin jumps on the far right →

This happens in all of Chrome 48.0.2564.116, Safari 8.0.8, and Firefox 44.0.2 on OS X 10.10.5 (14F27).