I am a Chinese and I don't think 青色 is the same as 绿色 or 蓝色. For me, 青色 is more a kind of blue. Personally, blue and 蓝色 also cover different series of blue color.
There is a very common proverb:
青,出于蓝,而胜于蓝
literally it means 青色 comes from blue but better than blue. Or more straightforward, 青色 is extracted from the blue plant(indigo) but is bluer than the plant. The next part is "冰，水为之，而寒于水"(ice comes from water but is colder than water).
There is a common color name in Chinese, 靛青，which is a kind of dark blue.
check the wikipedia link about the color. 青色 is the colors like Lapis lazuli, Salvia blue, Wedgwood blue or Slate blue.