What is the color legend in Android Studio kotlin code?

I'm learning kotlin currently and trying to understand the studio capabilities. I see that some of my code is in different color. While I did manage to figure out most of the color legend, Yellow and white are still a mistory to me:

• Orange = Kotlin reserved words

• Purple = member

• Gray = not in use

• Blue = input parameter name

• Green = string

• Yellow? (functions? some cases are still white)

• White? (default?)

  part1 part2

You can check out the color scheme of the IDE by opening the Settings and navigating to Editor > Color Scheme > Kotlin:

Here you can even click on parts of the code and it'll show you the relevant color setting.