Rectangle with sub entries uses different font style/color?

Question

Hello PlantUML team, can you help me?

If I uses rectangles with sub rectangles then a different font style (bold) and stereotype color is used.
Do I have to use additional skinparams? (rectangle with sub rectangle: stereotyp should be white and text not bold)

@startuml
skinparam rectangle<<container>> {
    StereotypeFontColor #FFFFFF
    FontColor #FFFFFF
    BackgroundColor #438DD5
    BorderColor #3C7FC0
}

rectangle "API Application\nProvides Internet Banking\nfunctionality via a\nJSON/HTTPS API." <<container>> as api {
}

rectangle "Web Application\nDelivers the static\ncontent and the Internet\nBanking single page\napplication." <<container>> as web {
    rectangle web_prop <<properties>> [
        Table web_prop...
    ]
}
@enduml

Thank you and best regards
Helmut