fixed 弹幕修复 bug

themes/Ying/assets/js/modules/floating-tools.js

@@ -58,11 +58,16 @@ window.initFloatingTools = function() {
             // Global Scroll Handler (Singleton)
             if (!window.backToTopScrollHandler) {
                 window.backToTopScrollHandler = function() {
+                    // Performance Optimization: Check scroll less frequently? 
+                    // No, rAF is best. But we can add a check if the button is even in DOM/Visible?
+                    // But checking DOM layout is expensive.
+                    // Keep rAF but ensure 'update' is light.
                     if (!ticking) {
                         window.requestAnimationFrame(update);
                         ticking = true;
                     }
                 };
+                // Use passive listener to prevent scroll blocking
                 window.addEventListener('scroll', window.backToTopScrollHandler, { passive: true });
             }