How can I style a JavaFX menu and its items in CSS?

Question

I\'ve got a MenuBar that is setup as follows in FXML:

Answer 1

.menu-bar {
    -fx-background-color: black ;
    -fx-opacity: 0.5;
    -fx-border-width: 2.0;

}
.menu-bar .label {
    -fx-font-size: 14.0 pt;
    -fx-font-family: "Bookman Old Style";
    -fx-text-fill: white;
    -fx-font-weight: bold; 
    -fx-padding: 10.0px;

}
.menu-bar .menu-button:hover, .menu-bar .menu-button:focused, .menu-bar .menu-button:showing {
    -fx-background: black ;
    -fx-opacity: 0.5;
    -fx-text-fill: white;
}

.menu-item {
    -fx-padding: 0.0em 0.0em 0.0em 0.0em;
    -fx-text-fill: black;
    -fx-background: darkgray ;
}
.menu-item .label{
    -fx-font-size: 14.0 pt;
    -fx-text-fill: black;
}
.menu-item .label:hover{
    -fx-font-size: 14.0 pt;
    -fx-background: black ;
    -fx-text-fill: white;
}
.context-menu {
    -fx-skin: "com.sun.javafx.scene.control.skin.ContextMenuSkin";
    -fx-background-color:white ;
    -fx-border-width: 0.2px;
    -fx-border-color: black;
    /** -fx-background-insets: 0.0, 1.0, 2.0;
    -fx-background-radius: 0.0 6.0 6.0 6.0, 0.0 5.0 5.0 5.0, 0.0 4.0 4.0 4.0;
    -fx-padding: 0.333333em 0.083333em 0.666667em 0.083333em; 
    -fx-opacity: 0.9;*/
}

Answer 2

I think you forgot the -fx-skin property in .context-menu.
Follow the How to style menu button and menu items.