Why not try teaming a black blazer with navy cargo pants? These two items are very functional and will look awesome when paired together. You can take a more relaxed approach with shoes and complement your ensemble with a pair of high top sneakers.
Navy Cargo Pants with High Top Sneakers Smart Casual Warm Weather Outfits
For an ensemble that's absolutely gasp-worthy, wear a navy trenchcoat with navy cargo pants. If you need to effortlessly play down this look with one single item, why not add a pair of high top sneakers to your outfit?