Colour of perfect place inside (6)
I believe the answer is:
purple
'colour' is the definition.
(purple is a kind of colour)
'perfect place inside' is the wordplay.
'perfect' becomes 'pure' (synonyms).
'place' becomes 'pl' (I've seen this in other clues).
'inside' indicates putting letters inside.
'pure' going around 'pl' is 'PURPLE'.
'of' acts as a link.
(Other definitions for purple that I've seen before include "Colour associated with imperial authority" , "Colour for aristocracy or emperors" , "Red and blue mixed" , "Colour between 14dn and blue" , "Colour obtained from mixing red with blue" .)