feat: 添加移动端下拉菜单和主题色设置

- 新增 MobileMenu 组件，小屏幕使用汉堡菜单替代多个按钮
- 重构 LanguageSettings 为统一下拉框样式
- 新增设置页面，支持主题色切换
- 翻译页添加源语言选择器
- 更新 8 种语言的 i18n 翻译

src/components/layout/LanguageSettings.tsx

@@ -1,81 +1,97 @@
 "use client";
 
-import { GhostLightButton } from "@/design-system/base/button";
-import { useState } from "react";
+import { useState, useEffect, useRef } from "react";
 import { Languages } from "lucide-react";
+import { cn } from "@/utils/cn";
+
+const languages = [
+  { code: "en-US", label: "English" },
+  { code: "zh-CN", label: "中文" },
+  { code: "ja-JP", label: "日本語" },
+  { code: "ko-KR", label: "한국어" },
+  { code: "de-DE", label: "Deutsch" },
+  { code: "fr-FR", label: "Français" },
+  { code: "it-IT", label: "Italiano" },
+  { code: "ug-CN", label: "ئۇيغۇرچە" },
+];
 
 export function LanguageSettings() {
-    const [showLanguageMenu, setShowLanguageMenu] = useState(false);
-    const handleLanguageClick = () => {
-        setShowLanguageMenu((prev) => !prev);
+  const [isOpen, setIsOpen] = useState(false);
+  const menuRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    const handleClickOutside = (event: MouseEvent) => {
+      if (menuRef.current && !menuRef.current.contains(event.target as Node)) {
+        setIsOpen(false);
+      }
     };
-    const setLocale = async (locale: string) => {
-        document.cookie = `locale=${locale}`;
-        window.location.reload();
+
+    if (isOpen) {
+      document.addEventListener("mousedown", handleClickOutside);
+    }
+
+    return () => {
+      document.removeEventListener("mousedown", handleClickOutside);
     };
-    return (
-        <>
-            <GhostLightButton
-                size="md"
-                onClick={handleLanguageClick}
+  }, [isOpen]);
+
+  useEffect(() => {
+    const handleEscape = (e: KeyboardEvent) => {
+      if (e.key === "Escape") setIsOpen(false);
+    };
+
+    if (isOpen) {
+      document.addEventListener("keydown", handleEscape);
+      return () => document.removeEventListener("keydown", handleEscape);
+    }
+  }, [isOpen]);
+
+  const setLocale = async (locale: string) => {
+    document.cookie = `locale=${locale}`;
+    window.location.reload();
+  };
+
+  return (
+    <div className="relative" ref={menuRef}>
+      <button
+        onClick={() => setIsOpen(!isOpen)}
+        className="flex items-center justify-center p-2 rounded-md text-white hover:bg-white/10 transition-colors"
+        aria-label="切换语言"
+        aria-expanded={isOpen}
+      >
+        <Languages size={20} />
+      </button>
+
+      <div
+        className={cn(
+          "absolute right-0 top-full mt-2 w-40 rounded-lg bg-white shadow-lg ring-1 ring-black/5 overflow-hidden transition-all duration-200 origin-top-right z-50",
+          isOpen
+            ? "opacity-100 scale-100"
+            : "opacity-0 scale-95 pointer-events-none"
+        )}
+        role="menu"
+      >
+        <div className="py-1">
+          {languages.map((lang) => (
+            <button
+              key={lang.code}
+              onClick={() => setLocale(lang.code)}
+              className="w-full flex items-center px-4 py-2.5 text-gray-700 hover:bg-gray-50 hover:text-gray-900 transition-colors text-left"
+              role="menuitem"
             >
-                <Languages size={20} />
-            </GhostLightButton>
-            <div className="relative">
-                {showLanguageMenu && (
-                    <div>
-                        <div className="absolute top-10 right-0 rounded-md shadow-md flex flex-col gap-2">
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("en-US")}
-                            >
-                                English
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("zh-CN")}
-                            >
-                                中文
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("ja-JP")}
-                            >
-                                日本語
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("ko-KR")}
-                            >
-                                한국어
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("de-DE")}
-                            >
-                                Deutsch
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("fr-FR")}
-                            >
-                                Français
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("it-IT")}
-                            >
-                                Italiano
-                            </GhostLightButton>
-                            <GhostLightButton
-                                className="w-full bg-primary-500"
-                                onClick={() => setLocale("ug-CN")}
-                            >
-                                ئۇيغۇرچە
-                            </GhostLightButton>
-                        </div>
-                    </div>
-                )}
-            </div></>
-    );
+              {lang.label}
+            </button>
+          ))}
+        </div>
+      </div>
+
+      {isOpen && (
+        <div
+          className="fixed inset-0 z-40"
+          onClick={() => setIsOpen(false)}
+          aria-hidden="true"
+        />
+      )}
+    </div>
+  );
 }