diff --git a/src/app/chat/chat-screen.tsx b/src/app/chat/chat-screen.tsx
index eb3f0d8f..a247f6db 100644
--- a/src/app/chat/chat-screen.tsx
+++ b/src/app/chat/chat-screen.tsx
@@ -2,11 +2,6 @@
 /**
  * ChatScreen 编排层
  *
- * 职责（本文件）：
- *   - 订阅 auth 状态机（loginStatus）—— 派生 isGuest / 派鉴权生命周期事件给 chat 机器
- *   - 屏幕生命周期事件（init / visible / invisible）
- *   - 不直接管理 WebSocket / 不直接读 AuthStorage（除 token 取值）
- *
  * 子组件职责：
  *   - ChatHeader：顶部栏（游客 banner / 菜单按钮）
  *   - ChatArea：消息列表
diff --git a/src/app/chat/components/chat-send-button.module.css b/src/app/chat/components/chat-send-button.module.css
index 0ceb4e4a..20a33e95 100644
--- a/src/app/chat/components/chat-send-button.module.css
+++ b/src/app/chat/components/chat-send-button.module.css
@@ -2,10 +2,11 @@
 
 .button {
   flex: 0 0 auto;
-  width: 48px;
+  width: 40px;
   height: 40px;
+  aspect-ratio: 1 / 1;
   border: 0;
-  border-radius: 9999px;
+  border-radius: 50%;
   background: var(--color-button-gradient-end, #fc69df);
   color: #fff;
   cursor: pointer;
diff --git a/src/app/chat/components/chat-send-button.tsx b/src/app/chat/components/chat-send-button.tsx
index d2f3fe90..d643b720 100644
--- a/src/app/chat/components/chat-send-button.tsx
+++ b/src/app/chat/components/chat-send-button.tsx
@@ -8,9 +8,9 @@
  *   - 默认：粉色背景 + 渐变边缘
  *   - 聚焦 / 激活：完整 primaryGradient（accent → 透明）
  *
- * 图标：lucide-react <Send />（tree-shakable，currentColor 继承父 color）
+ * 图标：lucide-react <ArrowUp />（tree-shakable，currentColor 继承父 color）
  */
-import { ArrowUp, Send } from "lucide-react";
+import { ArrowUp } from "lucide-react";
 
 import styles from "./chat-send-button.module.css";
 
diff --git a/src/app/chat/components/pwa-install-overlay.tsx b/src/app/chat/components/pwa-install-overlay.tsx
index dddfc007..fc9a71a2 100644
--- a/src/app/chat/components/pwa-install-overlay.tsx
+++ b/src/app/chat/components/pwa-install-overlay.tsx
@@ -14,6 +14,7 @@
  */
 import { useEffect } from "react";
 
+import { BrowserDetector } from "@/utils/browser-detect";
 import { SpAsyncUtil } from "@/utils/storage";
 import { pwaUtil } from "@/utils/pwa";
 
@@ -32,6 +33,7 @@ export function PwaInstallOverlay() {
       //    isInstalled() 检查 standalone display-mode（避免给已安装用户再弹）
       if (!pwaUtil.isSupported()) return;
       if (pwaUtil.isInstalled()) return;
+      if (BrowserDetector.isInAppBrowser()) return;
       // 提前挂 beforeinstallprompt 监听，避免用户点 OK 时事件已在更早时机丢失。
       pwaUtil.prepareInstallPrompt();
 
diff --git a/src/app/splash/components/splash-button.module.css b/src/app/splash/components/splash-button.module.css
index 6cece395..e24d7c37 100644
--- a/src/app/splash/components/splash-button.module.css
+++ b/src/app/splash/components/splash-button.module.css
@@ -9,7 +9,6 @@
 }
 
 .skip {
-  font-family: var(--font-athelas);
   font-size: var(--font-size-xxl);
   font-weight: 700;
   font-style: italic;
@@ -58,7 +57,6 @@
 }
 
 .facebookLabel {
-  font-family: var(--font-athelas);
   font-size: var(--font-size-xxl);
   font-weight: 700;
   color: #ffffff;
diff --git a/src/app/splash/components/splash-content.tsx b/src/app/splash/components/splash-content.tsx
index fdef115d..7dea7435 100644
--- a/src/app/splash/components/splash-content.tsx
+++ b/src/app/splash/components/splash-content.tsx
@@ -1,12 +1,5 @@
 /**
  * Splash 主内容文案
- *
- * 原始 Dart: lib/ui/splash/widgets/splash_content.dart
- *
- * 关键差异：
- *   - 使用 Athelas 字体（衬线体）
- *   - 标题加粗 + 斜体（与原 Dart 一致）
- *   - 颜色：白色（背景图上需高对比度）
  */
 import styles from "./splash-content.module.css";
 
diff --git a/src/app/splash/components/splash-logo.module.css b/src/app/splash/components/splash-logo.module.css
index 8e9829dd..6abba44b 100644
--- a/src/app/splash/components/splash-logo.module.css
+++ b/src/app/splash/components/splash-logo.module.css
@@ -7,6 +7,4 @@
   display: block;
   width: auto;
   height: auto;
-  /* Apple 平台 Athelas 渲染时仍可能需要 fallback */
-  font-family: var(--font-athelas, serif);
 }
diff --git a/src/app/splash/components/splash-screen.module.css b/src/app/splash/components/splash-screen.module.css
index d7a611da..84d90537 100644
--- a/src/app/splash/components/splash-screen.module.css
+++ b/src/app/splash/components/splash-screen.module.css
@@ -41,7 +41,6 @@
 
 .bottom {
   margin: var(--spacing-xxxl) 0 0 0;
-  font-family: var(--font-athelas);
   font-size: var(--font-size-md);
   font-weight: 400;
   line-height: 1.5;
diff --git a/src/core/fonts.ts b/src/core/fonts.ts
index 0807400b..0cdc0a53 100644
--- a/src/core/fonts.ts
+++ b/src/core/fonts.ts
@@ -9,7 +9,7 @@ import localFont from "next/font/local";
  * - 产出的 CSS 变量由 `globals.css` 桥接到 Tailwind（如 `font-sans`、`font-athelas`）。
  *
  * 注意：本文件不通过 `src/lib/index.ts` 桶导出，避免被误打进客户端 bundle。
- *       引用方式：`import { geistSans, geistMono, athelas } from "@/lib/fonts";`
+ *       引用方式：`import { geistSans, geistMono, athelas } from "@/core/fonts";`
  */
 
 const geistSans = Geist({
@@ -29,7 +29,7 @@ const geistMono = Geist_Mono({
  * 放置位置：/public/fonts/Athelas-*.ttf
  *
  * 路径计算（`next/font/local` 要求相对路径从调用文件出发）：
- *   src/lib/fonts.ts → ../../public/fonts/...
+ *   src/core/fonts.ts → ../../public/fonts/...
  */
 const athelas = localFont({
   src: [
diff --git a/src/core/net/config/api_config.ts b/src/core/net/config/api_config.ts
index dd1db524..c3ec69a7 100644
--- a/src/core/net/config/api_config.ts
+++ b/src/core/net/config/api_config.ts
@@ -4,8 +4,9 @@
  * 通过环境变量配置后端服务地址与超时时间。
  * 原始 Dart: lib/core/net/service_manager.dart
  */
+import { AppEnvUtil, type AppEnv } from "@/utils/app-env";
 
-export type AppEnv = "development" | "test" | "production";
+export type { AppEnv };
 
 export interface ApiConfig {
   /** 后端 API 基础 URL（含协议） */
@@ -33,9 +34,7 @@ export class TimeoutConstants {
  * 解析当前环境
  */
 export function getAppEnv(): AppEnv {
-  const env = process.env.NEXT_PUBLIC_APP_ENV;
-  if (env === "production" || env === "test") return env;
-  return "development";
+  return AppEnvUtil.current;
 }
 
 /**
diff --git a/src/data/dto/chat/guest_chat_quota.ts b/src/data/dto/chat/guest_chat_quota.ts
index 8bd7204d..19e63efd 100644
--- a/src/data/dto/chat/guest_chat_quota.ts
+++ b/src/data/dto/chat/guest_chat_quota.ts
@@ -6,6 +6,7 @@ import {
   type GuestChatQuotaInput,
   type GuestChatQuotaData,
 } from "@/data/schemas/chat/guest_chat_quota";
+import { AppEnvUtil } from "@/utils/app-env";
 
 export class GuestChatQuota {
   // 静态常量
@@ -13,7 +14,7 @@ export class GuestChatQuota {
   static readonly maxQuotaPerDayTest = 4;
 
   static readonly defaultTotalQuota = 50;
-  static readonly defaultTotalQuotaDev = 5;
+  static readonly defaultTotalQuotaTest = 5;
   static readonly quotaExhausted = 0;
 
   declare readonly remaining: number;
@@ -40,29 +41,22 @@ export class GuestChatQuota {
     return GuestChatQuota.quotaExhausted;
   }
 
-  /**
-   * 是否处于开发环境
-   */
-  static get isDevelopment(): boolean {
-    return process.env.NODE_ENV !== "production";
-  }
-
   /**
    * 获取当前环境的每日最大配额
    */
   static get threshold(): number {
-    return GuestChatQuota.isDevelopment
-      ? GuestChatQuota.maxQuotaPerDayTest
-      : GuestChatQuota.maxQuotaPerDay;
+    return AppEnvUtil.isProduction()
+      ? GuestChatQuota.maxQuotaPerDay
+      : GuestChatQuota.maxQuotaPerDayTest;
   }
 
   /**
    * 获取当前环境的总配额默认值
    */
   static get totalQuotaDefault(): number {
-    return GuestChatQuota.isDevelopment
-      ? GuestChatQuota.defaultTotalQuotaDev
-      : GuestChatQuota.defaultTotalQuota;
+    return AppEnvUtil.isProduction()
+      ? GuestChatQuota.defaultTotalQuota
+      : GuestChatQuota.defaultTotalQuotaTest;
   }
 
   /**
diff --git a/src/integrations/index.ts b/src/integrations/index.ts
index 9652de67..30be615f 100644
--- a/src/integrations/index.ts
+++ b/src/integrations/index.ts
@@ -2,5 +2,4 @@
  * @file Automatically generated by barrelsby.
  */
 
-export * from "./browser-detect";
 export * from "./media-recorder";
diff --git a/src/stores/auth/auth-events.ts b/src/stores/auth/auth-events.ts
index e01d58b9..c58b5b6a 100644
--- a/src/stores/auth/auth-events.ts
+++ b/src/stores/auth/auth-events.ts
@@ -12,7 +12,6 @@ export type AuthEvent =
   | { type: "AuthPanelModeChanged"; mode: AuthPanelMode }
   | { type: "AuthModeChanged"; mode: AuthMode }
   | { type: "AuthFormCleared" }
-  | { type: "AuthReset" }
   | { type: "AuthLogoutSubmitted" }
   /** App 启动时一次性派发 —— 读 storage 把 loginStatus 同步到状态机 */
   | { type: "AuthInit" }
diff --git a/src/stores/auth/auth-machine.ts b/src/stores/auth/auth-machine.ts
index 56efeb4d..9501502b 100644
--- a/src/stores/auth/auth-machine.ts
+++ b/src/stores/auth/auth-machine.ts
@@ -78,9 +78,6 @@ export const authMachine = setup({
             errorMessage: null,
           }),
         },
-        AuthReset: {
-          actions: assign(() => initialState),
-        },
         AuthLogoutSubmitted: "loggingOut",
         // 启动一次性 init：从 storage 同步 loginStatus 到状态机 —— 由 <AuthStatusChecker /> 派发
         AuthInit: "initializing",
diff --git a/src/stores/user/user-auth-sync.tsx b/src/stores/user/user-auth-sync.tsx
index 26911c9d..78710f42 100644
--- a/src/stores/user/user-auth-sync.tsx
+++ b/src/stores/user/user-auth-sync.tsx
@@ -19,6 +19,7 @@ export function UserAuthSync() {
   const userDispatch = useUserDispatch();
   const lastInitializedStatusRef = useRef<string | null>(null);
 
+  //TODO 在测位栏界面监听变化，监听登录状态的变化若发生变化，则需要分发 user init 事件
   useEffect(() => {
     if (loginStatus === "notLoggedIn" || loginStatus === "guest") {
       lastInitializedStatusRef.current = null;
diff --git a/src/tokens/typography.css b/src/tokens/typography.css
index 40352ca3..09459a8c 100644
--- a/src/tokens/typography.css
+++ b/src/tokens/typography.css
@@ -13,7 +13,6 @@
    */
   --font-system: var(--font-athelas), system-ui, -apple-system,
     BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
-  --font-athelas: "Athelas", serif;
 
   /* Tailwind 默认字体别名：font-sans → font-system */
   --font-sans: var(--font-system);
diff --git a/src/utils/app-env.ts b/src/utils/app-env.ts
index 96978737..1e7e5b74 100644
--- a/src/utils/app-env.ts
+++ b/src/utils/app-env.ts
@@ -3,13 +3,34 @@
  *
  * 原始 Dart: lib/utils/app_env_util.dart
  *
- * 替代 `AppEnvUtil.isDevelopment`：基于 Next.js 注入的 `process.env.NODE_ENV`。
+ * 基于 `.env*` 中的 `NEXT_PUBLIC_APP_ENV` 判断当前业务环境。
+ *
+ * 注意：该变量带 `NEXT_PUBLIC_` 前缀，可同时用于服务端和客户端代码。
  */
-export const isDevelopment = (): boolean =>
-  process.env.NODE_ENV !== "production";
+export type AppEnv = "development" | "test" | "production";
 
-export const isProduction = (): boolean =>
-  process.env.NODE_ENV === "production";
+export class AppEnvUtil {
+  private constructor() {}
 
-export const isTest = (): boolean =>
-  process.env.NODE_ENV === "test";
+  static get current(): AppEnv {
+    const env = process.env.NEXT_PUBLIC_APP_ENV;
+    if (env === "production" || env === "test") return env;
+    return "development";
+  }
+
+  static isDevelopment(): boolean {
+    return AppEnvUtil.current === "development";
+  }
+
+  static isProduction(): boolean {
+    return AppEnvUtil.current === "production";
+  }
+
+  static isTest(): boolean {
+    return AppEnvUtil.current === "test";
+  }
+
+  static canOutputLogs(): boolean {
+    return !AppEnvUtil.isProduction();
+  }
+}
diff --git a/src/integrations/browser-detect.ts b/src/utils/browser-detect.ts
similarity index 79%
rename from src/integrations/browser-detect.ts
rename to src/utils/browser-detect.ts
index fbcd1d5f..4f473193 100644
--- a/src/integrations/browser-detect.ts
+++ b/src/utils/browser-detect.ts
@@ -29,13 +29,4 @@ export const BrowserDetector = {
     return /WebView|; wv\)|FBAN|FBAV|MicroMessenger|Instagram|Line\//i.test(userAgent);
   },
 
-  /** 当前是否以 PWA standalone 模式运行 */
-  isPWAStandalone(): boolean {
-    if (typeof window === "undefined") return false;
-    return (
-      window.matchMedia?.("(display-mode: standalone)").matches === true ||
-      // iOS Safari 旧版
-      (navigator as Navigator & { standalone?: boolean }).standalone === true
-    );
-  },
 };
diff --git a/src/utils/logger.ts b/src/utils/logger.ts
index 87ac2d7c..3cd858f0 100644
--- a/src/utils/logger.ts
+++ b/src/utils/logger.ts
@@ -1,22 +1,22 @@
 import pino, { type Logger as PinoLogger, type LoggerOptions } from "pino";
 
-import { isProduction, isTest } from "./app-env";
+import { AppEnvUtil } from "./app-env";
 
 /**
  * 全局 pino root logger（单例，进程级复用）。
  *
- * 配置驱动（基于 `app-env.ts` 的 `isProduction()` / `isTest()`）：
- *   - production:  info 级别 + JSON（机器可解析，接入日志平台）
+ * 配置驱动（基于 `app-env.ts` 的 `AppEnvUtil`）：
+ *   - production:  silent（不输出日志）
  *   - test:        warn 级别（减少 vitest 噪音）
  *   - development: debug 级别 + ISO 时间戳（人眼友好）
  */
 const rootLogger: PinoLogger = pino(createLoggerOptions());
 
 function createLoggerOptions(): LoggerOptions {
-  if (isProduction()) {
-    return { level: "info" };
+  if (!AppEnvUtil.canOutputLogs()) {
+    return { level: "silent" };
   }
-  if (isTest()) {
+  if (AppEnvUtil.isTest()) {
     return { level: "warn" };
   }
   // development