Put the graham crackers, butter, brown sugar, and salt into a food processor. Process until a crumbly mixture forms.
Press the graham cracker mixture into the bottom of a 9 x 9 or 7 x 11 pan lined with foil. Place in the refrigerator while preparing the filling.
Put the cream cheese in a bowl and beat on medium speed. Add in the sweetened condensed milk and lemon juice and beat on medium speed until smooth. Set aside.
Meanwhile, pour the gelatin into a bowl with the boiling water, mix, and allow to sit for 2 minutes.
Pour the gelatin mixture into the cream cheese mixture and beat on medium speed until fluffy.
Pour the mixture into the crust and refrigerate for at least 8 hours before serving.