feat(AIChatPanel): update GradualBlur component to enhance blur effect; adjust ScrollArea scrollbar class handling

src/renderer/components/ai/AIChatPanel.tsx

@@ -204,19 +204,22 @@ export function AIChatPanel({
 
       {/* Scrollable messages area */}
       <div className="relative flex-1 min-h-0">
-        {/* Gradual blur at the top of messages */}
+        {/* Gradual blur at the bottom of messages */}
         {hasMessages && (
           <GradualBlur
-            position="top"
-            strength={2}
-            height="5rem"
-            divCount={6}
+            position="bottom"
+            strength={0.6}
+            height="4rem"
+            divCount={10}
+            curve="ease-out"
+            opacity={0.8}
             zIndex={20}
           />
         )}
         <ScrollArea
           className="h-full"
           viewportRef={messagesContainerRef}
+          scrollbarClassName={hasMessages ? 'z-30' : undefined}
           viewportClassName={
             isHomePage && !hasMessages
               ? '[&>div]:!flex [&>div]:!flex-col [&>div]:!min-h-full [&>div]:!justify-center'
@@ -382,10 +385,9 @@ export function AIChatPanel({
         </ScrollArea>
       </div>
 
-      {/* Fixed input — pinned to the bottom (hidden on initial state) */}
+      {/* Fixed input — pinned to the bottom, above the blur */}
       {hasMessages && (
-        <div className="absolute bottom-0 left-0 right-0 z-10 px-6 pb-5 pt-16 pointer-events-none">
-          <div className="absolute inset-x-0 top-0 h-full bg-gradient-to-b from-transparent via-background/60 to-background/90" />
+        <div className="absolute bottom-0 left-0 right-0 z-30 px-6 pb-5 pt-4 pointer-events-none">
           <div className="relative pointer-events-auto mx-auto max-w-3xl">
             <ChatInput
               input={input}