Matplotlib graphic placement varying from editor/browsers

See the attachment. On the left, in the editor. On the right, Safari.

On my old iPad I's running iOS 7, the graphic shows roughly where it is in the editor. But in Safari, its placement is "right" because I adjusted it in the editor so that it looks wrong, but displays where I want it.

I'd hate to have to create 2 different versions of this page to display properly on different devices. Any ideas?