In a medium saucepan, combine water, mango nectar, granulated sugar, dragonfruit powder, and citric acid. Heat over low heat, whisking continuously for about 3 minutes until dissolved. Remove from heat and let cool.

Pour the cooled refresher base into a large jar with a lid, sealing tightly to preserve flavors.

In a mason jar, mix oat milk, strawberry syrup, and soy milk. Froth the mixture for 20-30 seconds until thick and frothy.

In a cocktail shaker filled with ice, combine refresher base, coconut milk, and freeze-dried dragonfruit pieces. Shake for about 15 seconds until well mixed.

Strain the mixture into a tall glass filled with ice. Spoon the strawberry cold foam over the top and sprinkle with pink and green sprinkles.