I finished writing a book, and was planning to publish, but decided to go a self-publishing route so I can maintain better ownership of it. It's a children's textbook, so it needs to look professional, eye-catching, and quality design that allows children to navigate it clearly.
The problem is, I don't know much page and typography design. I know well enough to know how complex the art of laying out text can be. I have nice software that can get good results, but it still requires templates made by a designer, and the software has limited ones.
If I simply find a design I like in an existing book, is it illegal to copy the page dimensions, page numbering, font choice, and font sizes, for chapter titles, table of contents style, headings, etc.?