I hope you are well today and thank you for your question.
To achieve this, you have to remove the CSS code added in the custom CSS option of the theme settings as shown in the attached screenshot and add that CSS code in the style.css file of the Gillion child theme.
I did, that is blank (see attached). But the style id still is showing in the page code with nothing in it. Can I remove this, there s no reason for the style id if it is empty.