I am interested in the "Style Sheets" in Mathematica. But I have some difficulties.
1. I want to create a new style sheet. Following the instructions in the help document, I make a copy of the existing style sheet, for example "default.nb", called "myDefault.nb", and change some properties of the cells.
For example, I changed the text color from black to red, and the style sheet "myDefault.nb" worked well.
But, when I changed the FONT of the DisplayFormula into "Times New Roman", it didn't work. The FONT of the DisplayFormula in the notebook which applied the "myDefault.nb" style sheet is still the "Courier New".
I don't know what is wrong about my "myDefault.nb" style sheet.
2. I find the syle sheet file "APS_PhysRev.nb" from another wolfram product "Publicon". I copy the file "APS_PhysRev.nb" to the in the Mathematica directory, in "SystemFiles/FrontEnd/StyleSheets". But, When I apply this stylesheet, it doesn't work well again. I can't change the cell style any more. The list "Format->style->..." is empty except the command "other... Alt + 0".
What is wrong about "APS_PhysRev.nb".