The graphical listener can be styled in a few ways:

1. Using the ui.theme vocabulary to control the theme colors.

2. Setting attributes in interactor-style which styles the code editor, listener-word-style which styles triggered commands, listener-input-style which styles the previous input lines, and listener-output-style which styles rendered output.

3. Using set-listener-font to change the font of the open listener (applied to subsequent output lines).

Typically these settings all affect new listener sessions, or output. If you want them to be saved, you can add them to your ~/.factor-rc configuration file.