After I turned on compilation SCSS to CSS and then turned off again... it worked!
Hi Andrea.
Do not forget to cleanse the cache in Joomla, and not only in the browser.
To understand: template settings control variables in SCSS. When saving the settings compiling SCSS to CSS occurs. If Compilation SCSS to CSS is OFF many of the template settings will not work.
If you want to use template settings, then for the development period, this option must be enabled. After the end of the development, it can be turned off to improve the performance of the site.