God accepting drink in Borders (7)

I believe the answer is:

margins

'borders' is the definition.
('margin' can be a synonym of 'border')

'god accepting drink' is the wordplay.
'god' becomes 'mars' (Mars is an example).
'accepting' means one lot of letters goes inside another (inserted letters are accepted).
'drink' becomes 'gin' (gin is an alcoholic drink).
'mars' going around 'gin' is 'MARGINS'.

'in' is the link.

(Another definition for margins that I've seen is " Profits".)

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