Brighton have signed 18-year-old forward Charalampos Kostoulas for £29.78m (35m euros) from Greek side Olympiakos. The teenager has signed a five-year contract that will start on 1 July. The deal represents by some distance the highest fee ever received by a Greek club, beating the £16.6m Wolves paid to sign Daniel Podence from Olympiakos in 2020.