refactor(ui): redesign update notification to match Linear design system

- Replace gradient background with solid colors and subtle borders
- Remove decorative Info icon from settings panel that had no functionality
- Change update badge icon from Sparkles to Download for better clarity
- Simplify update button states with consistent blue primary color
- Remove all gradient effects in favor of flat design
- Unify hover states and transitions across all update-related UI

The update notification now seamlessly integrates with the app's Linear-inspired
aesthetic, providing a clean and non-intrusive user experience.

src/components/SettingsModal.tsx

@@ -1,5 +1,5 @@
 import { useState, useEffect } from "react";
-import { X, Info, RefreshCw, FolderOpen, Download, ExternalLink } from "lucide-react";
+import { X, RefreshCw, FolderOpen, Download, ExternalLink } from "lucide-react";
 import { getVersion } from "@tauri-apps/api/app";
 import "../lib/tauri-api";
 import { relaunchApp } from "../lib/updater";
@@ -192,11 +192,7 @@ export default function SettingsModal({ onClose }: SettingsModalProps) {
             </h3>
             <div className="p-4 bg-gray-100 dark:bg-gray-800 rounded-lg">
               <div className="flex items-start justify-between">
-                <div className="flex items-start gap-3">
-                  <Info
-                    size={18}
-                    className="text-gray-500 mt-0.5"
-                  />
+                <div>
                   <div className="text-sm">
                     <p className="font-medium text-gray-900 dark:text-gray-100">
                       CC Switch
@@ -222,10 +218,10 @@ export default function SettingsModal({ onClose }: SettingsModalProps) {
                     disabled={isCheckingUpdate || isDownloading}
                     className={`px-3 py-1.5 text-xs font-medium rounded-lg transition-all ${
                       isCheckingUpdate || isDownloading
-                        ? "bg-white dark:bg-gray-700 text-gray-400 dark:text-gray-500"
+                        ? "bg-gray-100 dark:bg-gray-700 text-gray-400 dark:text-gray-500 cursor-not-allowed"
                         : hasUpdate
-                        ? "bg-gradient-to-r from-blue-500 to-purple-500 hover:from-blue-600 hover:to-purple-600 text-white"
-                        : "bg-white dark:bg-gray-700 hover:bg-gray-50 dark:hover:bg-gray-600 text-blue-500 dark:text-blue-400"
+                        ? "bg-blue-500 hover:bg-blue-600 dark:bg-blue-600 dark:hover:bg-blue-700 text-white"
+                        : "bg-white dark:bg-gray-700 hover:bg-gray-50 dark:hover:bg-gray-600 text-blue-500 dark:text-blue-400 border border-gray-200 dark:border-gray-600"
                     }`}
                   >
                     {isDownloading ? (
@@ -241,7 +237,7 @@ export default function SettingsModal({ onClose }: SettingsModalProps) {
                     ) : hasUpdate ? (
                       <span className="flex items-center gap-1">
                         <Download size={12} />
-                        点击更新 {updateInfo?.availableVersion}
+                        更新到 v{updateInfo?.availableVersion}
                       </span>
                     ) : (
                       "检查更新"

src/components/UpdateBadge.tsx

@@ -1,9 +1,9 @@
-import { X, Sparkles } from "lucide-react";
+import { X, Download } from "lucide-react";
 import { useUpdate } from "../contexts/UpdateContext";
 
 interface UpdateBadgeProps {
   className?: string;
-  onClick?: () => void; // 点击徽标的回调（例如打开设置）
+  onClick?: () => void;
 }
 
 export function UpdateBadge({ className = "", onClick }: UpdateBadgeProps) {
@@ -17,12 +17,13 @@ export function UpdateBadge({ className = "", onClick }: UpdateBadgeProps) {
   return (
     <div
       className={`
-        flex items-center gap-2 px-3 py-1.5 
-        bg-gradient-to-r from-blue-500/20 to-purple-500/20
-        border border-blue-500/30
-        rounded-full text-xs
+        flex items-center gap-1.5 px-2.5 py-1
+        bg-white dark:bg-gray-800
+        border border-gray-200 dark:border-gray-700
+        rounded-lg text-xs
+        shadow-sm
         transition-all duration-200
-        ${onClick ? "cursor-pointer hover:border-blue-400/50" : ""}
+        ${onClick ? "cursor-pointer hover:bg-gray-50 dark:hover:bg-gray-750" : ""}
         ${className}
       `}
       role={onClick ? "button" : undefined}
@@ -35,10 +36,10 @@ export function UpdateBadge({ className = "", onClick }: UpdateBadgeProps) {
           onClick();
         }
       }}
-      >
-      <Sparkles className="w-3 h-3 text-blue-400 animate-pulse" />
-      <span className="text-gray-200 font-medium">
-        新版本 {updateInfo.availableVersion}
+    >
+      <Download className="w-3 h-3 text-blue-500 dark:text-blue-400" />
+      <span className="text-gray-700 dark:text-gray-300 font-medium">
+        v{updateInfo.availableVersion}
       </span>
       <button
         onClick={(e) => {
@@ -46,13 +47,14 @@ export function UpdateBadge({ className = "", onClick }: UpdateBadgeProps) {
           dismissUpdate();
         }}
         className="
-          -mr-1 p-0.5 rounded-full
-          hover:bg-white/10 transition-colors
-          focus:outline-none focus:ring-2 focus:ring-blue-500/50
+          ml-1 -mr-0.5 p-0.5 rounded
+          hover:bg-gray-100 dark:hover:bg-gray-700
+          transition-colors
+          focus:outline-none focus:ring-2 focus:ring-blue-500/20
         "
         aria-label="关闭更新提醒"
       >
-        <X className="w-3 h-3 text-gray-400 hover:text-gray-200" />
+        <X className="w-3 h-3 text-gray-400 dark:text-gray-500" />
       </button>
     </div>
   );