You should look up javafx. You can attach a css file to a GUI. it is fairly easy to use. I can give you some example code if you want.
These are some good tutorials on how to use it: https://www.youtube.com/watch?v=FLkOX4Eez6o
I use eclipse to create a css file right click the project -> select new -> other -> CSS file
import javafx.application.*; import java.text.*; import java.util.*; import javafx.event.*; import javafx.scene.*; import javafx.scene.control.*; import javafx.scene.layout.*; import javafx.scene.input.*; import javafx.stage.*; import javafx.geometry.*; public class Display extends Application{ public static void main(String[] args){ launch(args); } @Override public void start(Stage stage) throws Exception{ HBox root = new HBox(); Button button = new Button("button"); Label label = new Label("Label"); root.getChildren().addAll(button, label); Scene scene = new Scene(root, 700,300); scene.getStylesheets().add("Style.css"); stage.setScene(scene); stage.setTitle("Title"); stage.show(); } }
<———————————CSS File——————————>
.root{ -fx-background-color: linear-gradient(#383838, #838383); -fx-font-size: 11pt; } .label{ -fx-text-fill: #e8e8e8; } .button{ -fx-background-color: linear-gradient(#dc9556, #ab4642); -fx-background-radius: 100; } .text-area{ -fx-background-color: white; -fx-background-radius: 0; }