Make Separator / Whitespace Transparent (without a grey line for each separator)

Greetings!

I’d like a fix for the following issue:

Every time I include a Separator / Whitespace element, it appears as a light gray horizontal line across the page (or running across on both sides of content that is in front of it). Even when I choose “whitespace” from the dropdown menu for the element, this still happens.

I’ve done a bunch of different searches for fixes, but haven’t found one that makes them become transparent. It seems like this should be pretty easy to do with a custom CSS that applies to that particular element.

Thanks in advance for your assistance