- Update UI components to use transparent backgrounds instead of solid colors.

- Standardize text formatting and color usage across instrument clusters and gauges.
- Add new `BACKGROUND_COLOR_TRANSPARENT` definition in theme constants.
- Minor cleanup and adjustments for consistency in UI layouts.

crates/systems/src/systems.rs

@@ -120,7 +120,7 @@ pub fn update_system_display(
                 );
             }
             None => {
-                text.0 = "Select a system above to view details".to_string();
+                text.0 = "".to_string();
             }
         }
     }