Panel Settings
Styles
Panel Opener
Button to open panel content. You can use Box or Round design. To set icon/image size use Icon Size.
Panel Opener does have a Background color too. You can change that too using those controls after Icon Size.
Panel Content
You can set panel content background color, font family, font size from here.
Panel Title
You can set Panel Title background color, text color, font family, size, weight etc from here.
Content
You can change content’s Heading color, link normal and hover color from here.