Pulverize graham crackers in a food processor or blender.
In a large mixing bowl, combine graham cracker crumbs, sugar, brown sugar, and melted butter. Mix well with a fork.
Transfer mixture to a 9-inch springform pan. Press it firmly into the bottom of the pan and about 1 inch up the sides. Set aside.
Bring water to a boil in a small saucepan. Whisk gelatin in until it is dissolved. Set aside.
In a large mixing bowl, beat cream cheese until smooth.
Add powdered sugar, vanilla, lemon juice, sour cream, and gelatin mixture. Beat well.
Add cool whip and gently fold in.
Divide batter equally into four bowls. Add a drop or more of each color of food coloring gel to each bowl. The amount of food coloring used will depend on the potency you are using. Add until you reach your desired color.
Pour purple mixture over prepared crust and smooth it out. Place in the freezer for 15 minutes.
Repeat step 9 with the yellow, pink, and blue batters.
Cover with plastic wrap and chill for at least 4 hours before serving.