I was reading the highest rated answer of the question "Attractive Boxed Equations",
I don't understand the main code of the answer.
There are two problems for me:
- what do the commands with prefix "\my" do? For example, "\mytempbox", "\mytemplen", etc
- What's the meaning of the symbol "@"? How to use the command "\newcommand"?
I cannot find them on LaTeX reference card...
@, see this: Why do LaTeX internal commands have an@in them? – barbara beeton Apr 15 '20 at 19:51