When it comes to summer cocktails, seasonal and fruit-forward drinks are the move. Ask Julianna McIntosh, San Diego-based cocktail influencer and author of the forthcoming cocktail recipe book, “Pretty Simple Cocktails” (Clarkson Potter, $25). Here are three of her summer-inspired recipes, a trio that’s sure to help you stay cool and relaxed as you ride out the heat. Fro-Secco Spritz Get out the blender for this slushy drink that’s all about carefree vacation vibes, McIntosh writes.