MOSCOW >> Kylian Mbappe has electrified the World Cup with his speed and youthful exuberance. Luka Modric has coolly controlled matches in Russia with his graceful play in the middle.Whether France wins its second title in 20 years or Croatia raises the trophy for the first time Sunday at the Luzhniki Stadium in front of Russian President Vladimir Putin and nearly a billion television viewers could turn on the play of the two stars.