Guardiola says beating the in-form Seagulls at the AMEX Stadium was a huge moment for the Premier League champions.
The Citizens were off to a flyer in the opening 13 minutes when Ilkay Gundogan punished a spill by goalkeeper Robert Sanchez.
Phil Foden struck twice on 28 and 31 minutes respectively to give the visitors a three-goal buffer at halftime.
Manchester City dominated vast majority of the second half but Alexis Mac Allister pulled one back for the hosts before Riyad Mahrez settled Graham Potter’s side’s second defeat of the season.
"It's really good because I knew which team we faced,” said Guardiola when asked about Brighton.
"It was a good lesson, for 30 minutes they were better than us. This game must be played with the ball.
"We suffered and for the future we'll be good. "This is a huge victory for us. [To win here] is a big compliment for the team.
"We won the game because we have good players. Don't ask me too much about the decisions of the managers.
“They are aggressive and when they have the ball they know what they have to do. They have all the mechanisms of a big team.
"They have courage. I admire them for that. They play like a top four or five team.
