Hi there,
the body is the parent container for the web page.
All content is ( should be ) inside of the body element.
Lets start with the background color:
The body’s background color is the color behind the content.
You will only see this if either:
a. The Content is not full width – then the body color will be seen either side of the content.
b. the Content background is transparent.
Now for the content:
The body colors for any element eg. Text Color or Link Color will be inherited by any element within the body UNLESS you specifically set them to a different color.
For example: if you edited Colors > Content > Link color and pressed clear it would inherrit the Colors > Body > Link color.
Let me know if i understood correctly.