What are the primary colors of the Minnesota Vikings?

What are the primary colors of the Pittsburgh Steelers? What are the primary colors of the Las Vegas Raiders? What are the primary colors of the Denver Broncos? What are the primary colors of the Cleveland Browns? What are the primary colors of the Chicago Bears? Which team's mascot is named "Blitz"? Which team is nicknamed the "Big Blue"? Which team is often called "Gang Green"?