Can someone tell me why my code is rendering differently on jsfiddle than it is on jssbin?

[SamA74]

@asasass

What was causing the gap?

The exact same thing that was causing the gap more than 2 weeks ago.

[SOLVED] Trying to get: 5 block elements, and the 5 elements below that to stick to the middle element

The gap is from the default vertical alignment value of baseline for inline elements. Changing it to bottom will close the gap.