New features of the Las Vegas Raiders stadium were recently revealed. The ceiling is a high-strength translucent polymer that lets in natural light but keeps heat down in summer. Translucent stadium components will make the stadium appear black at day, but inside lights will be visible at night. The ribbon structure along the sides will ventilate fresh air in, relieve exhaust and drain water from the roof. The natural-grass field will grow outdoors on a 4-foot-high tray to be wheeled in on game day. An artificial-turf field will rest atop the stadium floor. Stadium capacity varies by event. For football games, it’s 62,500. Additional seats can be added for events like the Super Bowl bringing capacity to 70,000. The stadium will have nine clubs, three at field level, including two on opposite sides of the field at the 50-yard line. As some of the stadium is below-ground, half of fans can go down and the other half up to their seats, reducing congestion.