A package that facilitates the kind of theorem setup typically needed in American Mathematical Society publications. The package offers the theorem setup of the AMS document classes (amsart, amsbook, etc.) encapsulated in LaTeX package form so that it can be used with other document classes.
I am trying to create a customized "proof" environment attached to a theorem. It looks like this: So there is first the theorem, and then a gray bar starts on the inner margin. It ends, when the ...