Are there some magic lines to be placed in the preamble that would, like in CSS, specify how each generic section or subsection in the whole document should be formatted?
2 Answers
You can use the titlesec
package for this.
A short example would be \titleformat*{\section}{\itshape}
to change the style of \section
to \itshape
. See the package manual for more details.
See also:
What's the right way to change display of chapter headings?
How to format the chapter heading?
Formatting a \paragraph to look like a \section
or questions tagged with titlesec.
there are a lot of packages which support customizing titles and headers: