Let's math
Let's math

This centers the cross inside the button. I've done all the math. Don't
ask.

$offset makes the two bars cross at the correct relative position.
$fix-x and $fix-y are used to center the cross.

pycontw/pycontw2016,pycontw/pycontw2016,pycontw/pycontw2016,pycontw/pycontw2016