Tabs in wrong order

[evank]

My nav bar tabs are appearing in the opposite order of how I'm numbering them. Here's a screen capture of how I numbered them: http://vcfed.org/evan/tabs.png .... but you can see at http://www.vcfed.org/forum/forum.php that they are appearing in the opposite order! What am I doing wrong?

Even more strange: They were in the correct order before I moved the nav bar to the right side of the page per the advice here:
https://vborg.vbsupport.ru/showthread.php?t=322076

And sure enough, they go back to the correct order when I un-do that change.

Why are they backward only when the nav bar is on the right side of the page?