In the Computer Components and Concepts -> Intro to Computer Hardware video it is stated USB 3.1 will be colored purple. The book says it will be colored turquoise.

Many computers identify USB 3.0 with blue ports, but newer PC’s may. Mac computers have never used blue ports. When initially released, USB 3 ports were used alongside USB 2 ports. As USB 2.0 ports were commonly replaced with 3.0 ports, their color differentiation became less necessary. 

USB 3.0 ports are blue. Technically, USB 3.1 ports are teal, but may also look or be turquoise.