Remove from heat and allow the syrup to cool until it reaches room temperature and feels smooth, not sticky.

Pour the cooled syrup into a large pitcher, creating a slightly thick base.

Add the blue raspberry syrup and stir until the color becomes evenly vibrant and bright blue.

Pour in the fresh lemon juice, noticing the citrus aroma blending with the sweet syrup.

Add the remaining water and stir well until the mixture looks light, balanced, and evenly combined.

Toss in ice cubes and gently mix, allowing the drink to chill and slightly dilute for a smoother taste.

Add lemon slices for a fresh, fragrant garnish that enhances both appearance and flavor.

Serve immediately in glasses, ensuring the drink is cold and refreshing.