Panel won't align to the center of screen

Question

For some reason with flexbox it keeps aligning to the left or its doing something extra pulling it that way. I want the panel to be the full width of the screen and I don't know what is wrong.

Here is my code. It is happening in Bootply as well.

http://www.bootply.com/xrIqvTiDHW

Answer 1

需要保证金：0px;无论谁给了这个-1，谢谢你没用。