fix: clear CSS background on detail destroy so it doesn't linger

plugin.js

@@ -339,6 +339,18 @@
         };
 
         this.destroy = function () {
+            // Reset the background we set via CSS fallback so it doesn't linger
+            // after leaving the detail page (Lampa manages .background natively).
+            try {
+                var bgel = document.querySelector('.background');
+                if (bgel) {
+                    bgel.style.backgroundImage = '';
+                    bgel.style.filter = '';
+                    bgel.style.transform = '';
+                    bgel.style.opacity = '';
+                }
+                if (Lampa.Background && Lampa.Background.immediately) Lampa.Background.immediately('');
+            } catch (e) {}
         };
 
         this.start = function () {