How to split-screen with vertical separator

[UnknownSuperficialNight]

I'm attempting to create a split-screen layout similar to egui's SidePanel::left. However, the default separator takes up the entire width/height of the parent, which in this case is a ui.horizontal. As a result, the text is positioned on the right side and the separator only fills in by one character, due to the ui.horizontal aformentioned.

Code:

egui::Window::new("Settings").id(widget_ids[6]).resizable(true).show(ctx, |ui| {
                    //TODO Need to add editor for config_db in here
                    ui.horizontal(|ui| {
                        ui.add(egui::Separator::default().vertical().spacing(40.0));
                        // egui::Resize::default().default_size([550.0, 500.0]).show(ui, |ui| {
                        ui.vertical(|ui| {
                            if ui.add(egui::Checkbox::new(&mut self.display_image.lock().unwrap(), "Display album art while playing music")).clicked() {}
                            }
                            if ui.add(egui::Checkbox::new(&mut self.display_image_main_body.lock().unwrap(), "Display album art in the center")).clicked() {}
                        })
                    })
                });

here is a image for reference: