Hi Monika

Thank you for reaching out to us.

We don't have a specific documentation for this but I can explain how to find and copy the selectors you need to use to customize something.

Right-click on the part you wish to hide and inspect the element:

Then, when you hover over the code, that section will be highlighted in the modal. Right-click on the code that highlights the entire div, and go to copy/copy selector:

Paste that selector, and add "display: none !important;", like this for example if you want to hide something, different code would be applied if you want to change the color of course

#tab-extras {
display: none !important;
}

So, now Extras field is hidden:

Certain selectors can't be combined, so if it doesn't work when you separate them with a coma, simply add another selector below }

If this doesn't help either, we can recommend these services for customization

https://codeable.io/?ref=l1TW1

https://wpkraken.io/?tms-plugins