wgui: use dark mode

wgui/src/components/slider.rs

@@ -386,6 +386,7 @@ pub fn construct<U1, U2>(
 			WidgetLabelParams {
 				content: Translation::default(),
 				style: TextStyle {
+					color: Some(drawing::Color::new(0.0, 0.0, 0.0, 0.75)), // always black
 					weight: Some(FontWeight::Bold),
 					align: Some(HorizontalAlign::Center),
 					..Default::default()

wgui/src/globals.rs

@@ -6,12 +6,14 @@ use std::{
 use crate::{assets::AssetProvider, drawing, i18n::I18n};
 
 pub struct Defaults {
+	pub dark_mode: bool,
 	pub text_color: drawing::Color,
 }
 
 impl Default for Defaults {
 	fn default() -> Self {
 		Self {
+			dark_mode: true,
 			text_color: drawing::Color::new(0.0, 0.0, 0.0, 1.0),
 		}
 	}