java - Change fill color of JavaFX Charts -

i have outputted line chart using javafx. know how can change fill color (the orange) make transparent dynamically (possibly without use of css).

this code have till now;

@override public void start(stage stage) {     stage.settitle("ann");     //defining axes     final numberaxis xaxis = new numberaxis();     final numberaxis yaxis = new numberaxis();     xaxis.setlabel("epochs");     yaxis.setlabel("% of bad facts");     //creating chart     final linechart<number,number> linechart =              new linechart<number,number>(xaxis,yaxis);      linechart.settitle("bad facts vs epochs");       //defining series     xychart.series series = new xychart.series();      series.setname("badfacts/epoch");      (int k=0; k<epochs.length; k++) {         series.getdata().add(new xychart.data(epochs[k], badfacts[k]));     }      scene scene  = new scene(linechart,1500,1100);     linechart.getdata().add(series);     stage.setscene(scene);     stage.show(); } 

can hint please? thanks!