main.css:

.root {
    /* Fonts */
    -fx-font-family: serif;
    -fx-font-size: 15pt;
}

=> Font family is serif

But when I change the font-size of my text, the font family is overriden/returns to the system default (a non-serifed font).

http://imageshack.us/scaled/thumb/818/4gi5.png => the Text in the middle should still be serifed, only smaller.

FontTest.scala:

package fonttest

import scala.collection.JavaConverters._
import scalafx.Includes._

import scalafx.application.JFXApp
import scalafx.scene.Scene
import scalafx.stage.Stage
import scalafx.scene.layout.VBox
import scalafx.scene.text.Text

object FontTest extends JFXApp {

  stage = new JFXApp.PrimaryStage {
  
    width = 600
    height = 450
    
    scene = new Scene {
    
    stylesheets = Set("main.css")

      content = Set(new VBox {
          
          content = Set(
          
            new Text("Font"),
            
            new Text("Font") {
              style = "-fx-font-size: 11px;" // <= should be smaller, but still serifed like others
            },
            
            new Text("Font")
          )
        }
      )
    }
  }
}

https://docs.google.com/file/d/0B7lrDAvzeFVySmZ5Q2VxQlVEUE0/edit?usp=sharing => for the minimal source code + gradle build.