Hi Kirill,
I guess your request is beyond the scope of the plugin.
My suggestion would be following.
Create one shortcode for CSS, paste all the CSS your page needs in that.
Create one shortcode for HTML, paste all the HTML in that.
Use the CSS shortcode only “once” in the post/page.
Use the HTML shortcode multiple times as required.
By this way the CSS is not duplicated.
This is a manual operation, but you have to control and be aware of what CSS the page needs and create separate CSS group shortcodes accordingly.
Thanks,
Aakash