Put the code in the Top Admin Bar > Customize > Additional CSS > "Additional CSS" textarea, save it, delete all caches and check again.
In case you want to say thank you! 🙂 We'd really appreciate if you leave a good review on the plugin page. This is the best way to say thank you to this project and the support team.
if possible could you help with small CSS code to align all comments in one line
Regarding this one. No need to use the CSS code. Just uncheck/disable the "Enable threaded (nested) comments X levels deep" option. It's a native WordPress option and can be found in the Dashboard > Settings > Discussion admin page.
In case you want to say thank you! 🙂 We'd really appreciate if you leave a good review on the plugin page. This is the best way to say thank you to this project and the support team.