fix: use correct color for shadows (#70)

Uses the same alpha value as egui's light and dark themes.
The values are explicity set instead of using the old theme's values, as
otherwise when you go from egui default dark theme to Latte it would
end up with a shadow intended for dark mode.

src/lib.rs

@@ -99,6 +99,12 @@ fn make_widget_visual(
 impl Theme {
     fn visuals(&self, old: egui::Visuals) -> egui::Visuals {
         let is_latte = *self == LATTE;
+        let shadow_color = if is_latte {
+            egui::Color32::from_black_alpha(25)
+        } else {
+            egui::Color32::from_black_alpha(96)
+        };
+
         egui::Visuals {
             override_text_color: Some(self.text),
             hyperlink_color: self.rosewater,
@@ -127,12 +133,13 @@ impl Theme {
                     ..old.selection.stroke
                 },
             },
+
             window_shadow: epaint::Shadow {
-                color: self.base,
+                color: shadow_color,
                 ..old.window_shadow
             },
             popup_shadow: epaint::Shadow {
-                color: self.base,
+                color: shadow_color,
                 ..old.popup_shadow
             },
             dark_mode: !is_latte,