Saturday's goalless draw with the second-placed Seagulls means Cardiff are still in the relegation zone and one point adrift of safety.
It was Bluebirds' first clean sheet since the opening weekend of the season.
"We had to work really hard," said Warnock.
"There wasn't anybody who didn't give everything.
"We knew we had to because they're such a good team. They rip people apart. They had their moments but I never really felt threatened."
Cardiff had lost three of their previous four league games prior to Brighton's visit, but they produced a resolute display against Chris Hughton's side, who are now unbeaten in 13 Championship matches.
Although Warnock had overseen an initial improvement following his appointment in October, Cardiff had failed to keep a clean sheet in their first seven games under the former Crystal Palace and Sheffield United manager.
That prompted the 68-year-old to tease his centre-backs Sean Morrison and Sol Bamba that the Bluebirds would be unlikely to stop high-flying Brighton from scoring at Cardiff City Stadium.
"The two centre-halves, I might owe them a few quid because we haven't had a clean sheet," Warnock added.
"I said: 'We won't get one today with you lot, will we? The way we defend.' And they both came up to me after the game and said: 'What were you saying gaffer?' So it was good to see that."
Cardiff were without striker Rickie Lambert against Brighton after the England international was unable to train on Thursday.
Warnock does not know the extent of Lambert's injury but was pleased with the performance of his understudy, Frederic Gounongbe, who made his first start under Warnock on Saturday.
"Fred's done well in training and I thought he did well for an hour [against Brighton]. It's hard, that sole role up there [in attack] and everybody's got to contribute, and I thought we did," said the Cardiff manager.
"To think we lost [Lee] Peltier, who's been our best defender, and Rickie, who's on a goalscoring spree, it was difficult, but all credit to the lads who came in."
Neil Warnock praised Cardiff City's defensive qualities after a first clean sheet of his tenure kept Championship title contenders Brighton at bay.