Millions of Americans order hamburgers, pizza, fried chicken, coffee or some other item every day from one of almost 300,000 fast-food restaurants across the country. But some fast-food chains are losing customers and closing stores as consumers flock to fast-casual restaurants that emphasize distinctive, creatively prepared food and eco-friendly production. To compete, major fast-food companies have begun offering healthier menu items in addition to the high-calorie options that remain popular with many consumers. Some restaurants also are working to reduce pollution linked to their operations. And certain chains, including White Castle, serve plant-based, meatless burgers designed to appeal to health-conscious and environmentally minded consumers. In the race to stay relevant with teens and young adults, McDonald's and other chains are relying increasingly on mobile delivery apps and buzz-worthy internet promotions. Rising labor costs, meanwhile, have led to higher prices for some fast-food items, and to predictions that the industry will rely more on robots and less on human workers in the future.