Green décor finely tweaked (3-8)
I believe the answer is:
eco-friendly
'green' is the definition.
(I've seen this before)
'decor finely tweaked' is the wordplay.
'tweaked' is an anagram indicator (I've seen this in other clues).
'decor'+'finely'='decorfinely'
'decorfinely' is an anagram of 'ECO-FRIENDLY'.
(Other definitions for eco-friendly that I've seen before include "In harmony with the environment" , "Not harmful to the environment" .)