Colour scheme in wide corridor (5)
I believe the answer is:
decor
'colour scheme' is the definition.
(I've seen this before)
'in wide corridor' is the wordplay.
'in' indicates the answer is hidden within the clue.
'DECOR' is hidden in the letters of 'wide corridor'.
(Other definitions for decor that I've seen before include "Scheme of interior furnishings" , "Colour-scheme etc of a room" , "Interior layout and furnishings" , "Style of furnishing etc used in room" , "Credo (anag.)" .)