Customizing appearance of code blocks, or notes in general for all notes in my notebook

[Calab]

I want to make a couple small formatting changes in my notebook. For example, I would like any code block text to be smaller, and possibly disable word wrapping.

I've read the section about Themes and Custom CSS, but I cannot get it to work.

• I've created a code note at root labelled CSS
• Under Owned Attributes I have added the label appCss
• I've placed some simple CSS into the note
• I've reloaded the book with Ctrl-R
  ...but nothing changes.

[Calab]

I found my issue... Under Basic Properties I did not have CSS selected.

CSS did not appear because I disabled that language under the options. Once I enabled it again I could set the note type to CSS.