mandala_contributor_corbel_gateways_reward_effect

mandala_contributor_corbel_gateways_reward_effect = { 
	add_prestige = {
		value = {
			add = mandala_contribution_medium_prestige_reward
			multiply = 1.75
			#Rounds up to the closest number divisible by 5
			divide = 5
			ceiling = yes
			multiply = 5
		}
	}
	add_piety_experience = {
		value = {
			add = mandala_contribution_medium_dynasty_reward
			multiply = 1.75
			#Rounds up to the closest number divisible by 5
			divide = 5
			ceiling = yes
			multiply = 5
		}
	}
}

As written in game/common/scripted_effects/tgp_mandala_scripted_effects.txt.