Brighton's superb start to the Premier League season continued as they held off a late Leicester rally to move up to third place in the table.
The Foxes twice thought they had rescued a point in the closing stages but Ademola Lookman and Wilfred Ndidi both saw goals chalked off for Harvey Barnes straying offside.
Brighton bossed the opening hour but needed a controversial penalty to set them on their way, Neal Maupay scoring his third goal of the season from the spot after Jannik Vestergaard's handball.
Vestergaard argued a foul by Maupay led him to handle Shane Duffy's header but, after lengthy deliberations, referee Stuart Attwell awarded a spot-kick.