diff --git a/agent/src/main.rs b/agent/src/main.rs
index 0dcff3d..5e5fe00 100644
--- a/agent/src/main.rs
+++ b/agent/src/main.rs
@@ -2315,20 +2315,16 @@ fn main() {
 #[cfg(test)]
 mod tests {
     use clap::Parser;
-    use std::net::TcpListener;
-    use std::thread;
     use std::time::{Duration, Instant};
 
     use super::{
-        ack_interval, advance_deadline, agent_artifact_name, clock_offset_from_http_date,
-        corrected_timestamp, executable_format_valid, gpu_name_from_uevent, is_public_probe_ip,
-        live_batch_interval, live_endpoint, live_update_payload, median, mirrored_download_url,
+        ack_interval, advance_deadline, clock_offset_from_http_date, corrected_timestamp,
+        gpu_name_from_uevent, is_public_probe_ip, live_endpoint, live_update_payload,
         normalized_version, parse_lspci_gpu_names, parse_probe_target,
         parse_system_profiler_gpu_names, ping_latency, prune_report_samples, release_asset_sha256,
-        report_retry_delay, sanitize_latency_tasks, selected_interface, tcp_latency_probe_address,
-        valid_endpoint, valid_sample_schedule, version_triplet, CliOptions, ClockCalibration,
+        sanitize_latency_tasks, valid_endpoint, version_triplet, CliOptions, ClockCalibration,
         GithubReleaseAsset, LatencyResult, LatencyTask, LiveAck, Report, CLOCK_CALIBRATION_MAX_AGE,
-        MAX_LATENCY_TASKS, MAX_PENDING_LATENCY_RESULTS, PROBE_ATTEMPTS,
+        MAX_LATENCY_TASKS, MAX_PENDING_LATENCY_RESULTS,
     };
 
     #[cfg(any(target_os = "windows", target_os = "macos"))]
@@ -2336,13 +2332,6 @@ mod tests {
     #[cfg(target_os = "linux")]
     use super::disk_device;
 
-    #[test]
-    fn selects_network_interfaces() {
-        assert!(selected_interface("eth0", ""));
-        assert!(!selected_interface("lo", ""));
-        assert!(selected_interface("ens3", "eth0, ens3"));
-    }
-
     #[test]
     fn parses_platform_gpu_names() {
         let lspci = "00:02.0 VGA compatible controller: Intel Corporation CometLake-S GT2 [UHD Graphics 630] (rev 05)\n\
@@ -2421,17 +2410,6 @@ mod tests {
         assert!(!valid_endpoint("https://bad host.example"));
     }
 
-    #[test]
-    fn builds_mirrored_download_urls() {
-        let release =
-            "https://github.com/imengying/NodeFlare/releases/download/v1.2.3/agent-linux-x86_64";
-        assert_eq!(mirrored_download_url("", release), release);
-        assert_eq!(
-            mirrored_download_url("https://mirror.example.com/", release),
-            format!("https://mirror.example.com/{release}")
-        );
-    }
-
     #[test]
     fn builds_live_websocket_endpoints() {
         assert_eq!(
@@ -2577,30 +2555,6 @@ mod tests {
         assert!(!sanitized.iter().any(|task| task.id == "bad"));
     }
 
-    #[test]
-    fn backs_off_failed_reports() {
-        assert_eq!(report_retry_delay(0, 60), Duration::from_secs(60));
-        assert_eq!(report_retry_delay(1, 60), Duration::from_secs(5));
-        assert_eq!(report_retry_delay(4, 60), Duration::from_secs(40));
-        assert_eq!(report_retry_delay(20, 60), Duration::from_secs(300));
-    }
-
-    #[test]
-    fn validates_sample_schedules() {
-        assert!(valid_sample_schedule(3600, 5));
-        assert!(!valid_sample_schedule(3600, 4));
-        assert!(!valid_sample_schedule(60, 0));
-        assert!(!valid_sample_schedule(10, 1));
-    }
-
-    #[test]
-    fn batches_live_samples_at_one_fifteenth_of_the_history_interval() {
-        assert_eq!(live_batch_interval(60, 1), Duration::from_secs(4));
-        assert_eq!(live_batch_interval(60, 5), Duration::from_secs(5));
-        assert_eq!(live_batch_interval(120, 1), Duration::from_secs(8));
-        assert_eq!(live_batch_interval(3_600, 1), Duration::from_secs(60));
-    }
-
     #[test]
     fn advances_collection_deadlines_without_drift() {
         let start = Instant::now();
@@ -2661,23 +2615,6 @@ mod tests {
         assert_eq!(connection_counts_from_netstat(output), (2, 1));
     }
 
-    #[test]
-    fn selects_current_platform_artifact() {
-        #[cfg(target_os = "linux")]
-        assert!(agent_artifact_name().is_some_and(|name| name.starts_with("agent-linux-")));
-        #[cfg(target_os = "windows")]
-        assert_eq!(agent_artifact_name(), Some("agent-windows-x86_64.exe"));
-        #[cfg(all(target_os = "macos", target_arch = "aarch64"))]
-        assert_eq!(agent_artifact_name(), Some("agent-macos-aarch64"));
-    }
-
-    #[test]
-    fn recognizes_current_executable_format() {
-        assert!(executable_format_valid(
-            &std::env::current_exe().expect("current executable")
-        ));
-    }
-
     #[test]
     fn parses_probe_targets() {
         assert_eq!(
@@ -2729,27 +2666,6 @@ mod tests {
         }
     }
 
-    #[test]
-    fn calculates_median() {
-        assert_eq!(median(&mut [4.0, 1.0, 3.0]), 3.0);
-        assert_eq!(median(&mut [4.0, 1.0, 3.0, 2.0]), 2.5);
-    }
-
-    #[test]
-    fn measures_local_tcp_latency() {
-        let listener = TcpListener::bind("127.0.0.1:0").expect("bind test listener");
-        let address = listener.local_addr().expect("listener address");
-        let accepter = thread::spawn(move || {
-            for _ in 0..PROBE_ATTEMPTS {
-                listener.accept().expect("accept probe connection");
-            }
-        });
-        let (latency, loss) = tcp_latency_probe_address(&address);
-        accepter.join().expect("join listener");
-        assert!(latency >= 0.0);
-        assert_eq!(loss, 0.0);
-    }
-
     #[test]
     fn parses_ping_latency() {
         assert_eq!(ping_latency("64 bytes time=12.34 ms"), Some(12.34));
diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 9c132b8..3560035 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -2,6 +2,7 @@ import { KeyRound, Megaphone, Moon, Search, Sun, UserCircle } from "lucide-react
 import { lazy, Suspense, useCallback, useEffect, useMemo, useRef, useState, type FormEvent } from "react";
 import { api, ApiError, setToken } from "./api";
 import { NodeCard } from "./components/NodeCard";
+import { SiteLogo } from "./components/SiteLogo";
 import { StatsBar } from "./components/StatsBar";
 import { TurnstileWidget } from "./components/TurnstileWidget";
 import { demoConfig, demoExchangeRates, demoServers } from "./demo";
@@ -279,8 +280,8 @@ export default function App() {
       link.rel = "icon";
       document.head.append(link);
     }
-    link.href = config.favicon_url || "/logo.svg";
-  }, [config.favicon_url]);
+    link.href = config.favicon_url || config.logo_url || "/logo.svg";
+  }, [config.favicon_url, config.logo_url]);
 
   useEffect(() => {
     const media = matchMedia("(prefers-color-scheme: dark)");
@@ -446,7 +447,7 @@ export default function App() {
       <div className="theme-background" style={background ? { backgroundImage: `url(${JSON.stringify(background)})`, opacity: 1 } : undefined} />
       <header className="site-header">
         <div className="container header-inner">
-          <div className="brand"><img src="/logo.svg" alt="" width="36" height="36" /><strong>{config.site_name}</strong></div>
+          <div className="brand"><SiteLogo src={config.logo_url} alt="" width="36" height="36" /><strong>{config.site_name}</strong></div>
           <div className="header-actions">
             <button className="icon-btn" onClick={toggleTheme} title={dark ? ui(config.locale, "浅色主题", "Light theme") : ui(config.locale, "深色主题", "Dark theme")}>{dark ? <Sun size={18} /> : <Moon size={18} />}</button>
             <button className="icon-btn" onClick={openAdmin} title={ui(config.locale, "进入后台", "Administration")}><UserCircle size={18} /></button>
@@ -458,21 +459,21 @@ export default function App() {
         {config.site_announcement ? <div className="site-announcement"><Megaphone size={16} /><span>{config.site_announcement}</span></div> : null}
         {needsLogin ? (
           <section className="dashboard-login-gate glass-panel">
-            <img src="/logo.svg" alt="" width="46" height="46" />
+            <SiteLogo src={config.logo_url} alt="" width="46" height="46" />
             <div className="dashboard-login-copy"><h1>{ui(config.locale, "登录仪表盘", "Sign in to dashboard")}</h1><p>{ui(config.locale, "此仪表盘仅限登录后访问", "This dashboard requires an administrator sign-in")}</p></div>
             <form className="dashboard-login-form" onSubmit={(event) => void loginDashboard(event)}>
               <label><span>{ui(config.locale, "用户名", "Username")}</span><input autoFocus autoComplete="username" value={loginUsername} onChange={(event) => setLoginUsername(event.target.value)} required /></label>
               <label><span>{ui(config.locale, "密码", "Password")}</span><input type="password" autoComplete="current-password" value={loginPassword} onChange={(event) => setLoginPassword(event.target.value)} required /></label>
-              {config.turnstile_login_enabled ? <div className="dashboard-login-turnstile"><TurnstileWidget siteKey={config.turnstile_site_key} theme={dark ? "dark" : "light"} resetKey={loginTurnstileReset} onVerify={setLoginTurnstileToken} onError={setError} /></div> : null}
+              {config.turnstile_login_enabled ? <div className="dashboard-login-turnstile"><TurnstileWidget siteKey={config.turnstile_site_key} action="admin-login" theme={dark ? "dark" : "light"} resetKey={loginTurnstileReset} onVerify={setLoginTurnstileToken} onError={setError} /></div> : null}
               {error ? <p className="form-error">{error}</p> : null}
               <button className="primary-btn dashboard-login-submit" disabled={loginBusy || (config.turnstile_login_enabled && !loginTurnstileToken)} type="submit"><KeyRound size={16} />{loginBusy ? ui(config.locale, "登录中", "Signing in") : ui(config.locale, "登录", "Sign in")}</button>
             </form>
           </section>
         ) : needsVerification ? (
           <section className="verification-gate">
-            <img src="/logo.svg" alt="" width="52" height="52" />
+            <SiteLogo src={config.logo_url} alt="" width="52" height="52" />
             <div><h1>{ui(config.locale, "访问验证", "Access verification")}</h1><p>{config.site_name}</p></div>
-            {config.turnstile_site_key ? <TurnstileWidget siteKey={config.turnstile_site_key} theme={dark ? "dark" : "light"} onVerify={(token) => void verifyDashboard(token)} onError={setError} /> : <p className="form-error">{ui(config.locale, "Turnstile 尚未正确配置", "Turnstile is not configured")}</p>}
+            {config.turnstile_site_key ? <TurnstileWidget siteKey={config.turnstile_site_key} action="public-dashboard" theme={dark ? "dark" : "light"} onVerify={(token) => void verifyDashboard(token)} onError={setError} /> : <p className="form-error">{ui(config.locale, "Turnstile 尚未正确配置", "Turnstile is not configured")}</p>}
             {verificationBusy ? <span className="verification-status">{ui(config.locale, "正在验证", "Verifying")}</span> : null}
             {error ? <p className="form-error">{error}</p> : null}
           </section>
diff --git a/frontend/src/admin-main.tsx b/frontend/src/admin-main.tsx
index d3bfac4..67338e6 100644
--- a/frontend/src/admin-main.tsx
+++ b/frontend/src/admin-main.tsx
@@ -43,6 +43,15 @@ function AdminApp() {
   useEffect(() => {
     document.title = config ? `管理面板 · ${config.site_name}` : "管理面板";
   }, [config]);
+  useEffect(() => {
+    let link = document.querySelector<HTMLLinkElement>('link[rel="icon"]');
+    if (!link) {
+      link = document.createElement("link");
+      link.rel = "icon";
+      document.head.append(link);
+    }
+    link.href = config?.favicon_url || config?.logo_url || "/logo.svg";
+  }, [config?.favicon_url, config?.logo_url]);
 
   if (error) return <div className={`admin-loading ${dark ? "admin-dark" : ""}`}><span>{error}</span><button className="secondary-btn" onClick={() => void loadConfig()}>重试</button></div>;
   if (!config) return <div className={`admin-loading ${dark ? "admin-dark" : ""}`}>正在加载管理面板</div>;
diff --git a/frontend/src/components/AdminPanel.tsx b/frontend/src/components/AdminPanel.tsx
index 2af4775..30ab90f 100644
--- a/frontend/src/components/AdminPanel.tsx
+++ b/frontend/src/components/AdminPanel.tsx
@@ -37,6 +37,8 @@ import { derivePassword } from "../password";
 import { ASSET_CURRENCIES, type AdminServer, type CloudflareUsage, type Config, type DatabaseStats, type ExchangeRates, type ServerInput, type Settings, type Theme, type ThemeSettingField, type ThemeSettingsSchema, type ThemeSettingValue } from "../types";
 import { Checkbox } from "./Checkbox";
 import { TurnstileWidget } from "./TurnstileWidget";
+import { useDialog } from "./useDialog";
+import { SiteLogo } from "./SiteLogo";
 import { LatencyManager } from "./LatencyManager";
 import { AlertRuleManager } from "./AlertRuleManager";
 import { Flag } from "./Flag";
@@ -499,6 +501,8 @@ export function AdminPanel({
     }
     return `curl -fsSL ${installer}/agent.sh | sudo sh -s -- -e ${shellLiteral(origin)} -t ${shellLiteral(install.agent_token)}${shellMirror}`;
   }, [install, installPlatform]);
+  const serverDialog = useDialog<HTMLFormElement>(editing !== null, () => setEditing(null));
+  const installDialog = useDialog<HTMLElement>(Boolean(installCommand), () => setInstall(null));
 
   const toggleSelected = (id: string) => setSelectedIds((current) => current.includes(id) ? current.filter((value) => value !== id) : [...current, id]);
   const allSelected = servers.length > 0 && selectedIds.length === servers.length;
@@ -513,32 +517,33 @@ export function AdminPanel({
     setNotice("");
     setError("");
   };
+  const siteLogoUrl = settings ? settings.logo_url : config.logo_url;
 
   return (
     <div className={`admin-page ${dark ? "admin-dark" : ""}`}>
       {error ? <div className="admin-toast error" role="alert" aria-live="assertive"><CircleAlert aria-hidden="true" /><span>{error}</span></div>
         : notice ? <div className="admin-toast" role="status" aria-live="polite"><CircleCheck aria-hidden="true" /><span>{notice}</span></div> : null}
       {!authenticated ? <div className="admin-login-stage">
-        <button className="admin-back" type="button" onClick={onClose}><ArrowLeft size={14} />返回仪表盘</button>
+        <button className="admin-back" type="button" onClick={onClose}><ArrowLeft size={14} />返回</button>
         <button className="admin-login-theme" type="button" onClick={onToggleTheme} title={dark ? "切换浅色主题" : "切换深色主题"}>{dark ? <Sun size={16} /> : <Moon size={16} />}</button>
         <form className="login-form glass-panel" onSubmit={login}>
-          <img src="/logo.svg" alt="" width="48" height="48" />
+          <SiteLogo src={siteLogoUrl} alt="" width="48" height="48" />
           <div className="login-copy"><h1>管理员登录</h1></div>
           <label><span>用户名</span><input autoFocus type="text" autoComplete="username" value={username} onChange={(event) => setUsername(event.target.value)} required /></label>
           <label><span>密码</span><input type="password" autoComplete="current-password" value={password} onChange={(event) => setPassword(event.target.value)} required /></label>
-          {config.turnstile_login_enabled || config.turnstile_enabled ? <div className="login-turnstile"><TurnstileWidget siteKey={config.turnstile_site_key} theme={dark ? "dark" : "light"} resetKey={turnstileReset} onVerify={setTurnstileToken} onError={setError} /></div> : null}
+          {config.turnstile_login_enabled || config.turnstile_enabled ? <div className="login-turnstile"><TurnstileWidget siteKey={config.turnstile_site_key} action="admin-login" theme={dark ? "dark" : "light"} resetKey={turnstileReset} onVerify={setTurnstileToken} onError={setError} /></div> : null}
           <button className="primary-btn login-submit" disabled={busy || ((config.turnstile_login_enabled || config.turnstile_enabled) && !turnstileToken)} type="submit"><KeyRound size={16} />{busy ? "验证中" : "登录"}</button>
         </form>
       </div> : <section className="admin-shell" aria-label="管理面板">
         <header className="admin-topbar">
           <div className="admin-brand">
-            <img src="/logo.svg" alt="" width="36" height="36" />
+            <SiteLogo src={siteLogoUrl} alt="" width="36" height="36" />
             <strong>{config.site_name}</strong>
           </div>
           <div className="admin-topbar-actions">
             <button type="button" onClick={onToggleTheme} title={dark ? "切换浅色主题" : "切换深色主题"} aria-label={dark ? "切换浅色主题" : "切换深色主题"}>{dark ? <Sun size={17} /> : <Moon size={17} />}</button>
-            <button type="button" onClick={onClose} title="返回前台" aria-label="返回前台"><ArrowLeft size={17} />返回前台</button>
-            <button type="button" onClick={() => void logout()} title="退出登录" aria-label="退出登录"><LogOut size={17} />退出登录</button>
+            <button type="button" onClick={onClose} title="主页" aria-label="主页"><ArrowLeft size={17} />主页</button>
+            <button type="button" onClick={() => void logout()} title="退出" aria-label="退出"><LogOut size={17} />退出</button>
           </div>
         </header>
 
@@ -605,20 +610,20 @@ export function AdminPanel({
                     <div className="form-actions"><button className="primary-btn" disabled={busy}><Plus size={16} />添加主题</button></div>
                   </form>
                 </div>
-              ) : settings ? (
+              ) : settings && tab !== "about" ? (
                 <form className="settings-form" onSubmit={saveSite}>
                   {tab === "appearance" ? <>
                     <div className="section-title"><Eye size={15} />外观与展示</div>
                     <div className="form-grid"><label><span>站点名称</span><input required value={settings.site_name} onChange={(event) => updateSettings("site_name", event.target.value)} /></label><label><span>站点描述</span><input value={settings.site_description} onChange={(event) => updateSettings("site_description", event.target.value)} /></label></div>
                     <label><span>站点公告</span><textarea rows={3} maxLength={1000} value={settings.site_announcement} onChange={(event) => updateSettings("site_announcement", event.target.value)} /></label>
-                    <div className="form-grid"><label><span>界面语言</span><select value={settings.locale} onChange={(event) => updateSettings("locale", event.target.value as Settings["locale"])}><option value="zh-CN">简体中文</option><option value="en">English</option></select></label><label><span>站点图标地址</span><input type="url" value={settings.favicon_url} onChange={(event) => updateSettings("favicon_url", event.target.value)} placeholder="https://example.com/favicon.png" /></label></div>
+                    <div className="form-grid three"><label><span>界面语言</span><select value={settings.locale} onChange={(event) => updateSettings("locale", event.target.value as Settings["locale"])}><option value="zh-CN">简体中文</option><option value="en">English</option></select></label><label><span>站点 Logo 地址</span><input type="url" maxLength={1000} value={settings.logo_url} onChange={(event) => updateSettings("logo_url", event.target.value)} placeholder="https://example.com/logo.svg" /></label><label><span>浏览器图标地址</span><input type="url" maxLength={1000} value={settings.favicon_url} onChange={(event) => updateSettings("favicon_url", event.target.value)} placeholder="https://example.com/favicon.png" /></label></div>
                     <div className="form-grid"><label><span>离线判定（秒）</span><input type="number" min="30" max="3600" value={settings.offline_threshold_seconds} onChange={(event) => updateSettings("offline_threshold_seconds", Number(event.target.value))} /></label><label><span>历史保留（天）</span><input type="number" min="1" max="365" value={settings.history_retention_days} onChange={(event) => updateSettings("history_retention_days", Number(event.target.value))} /></label></div>
                   </> : null}
 
                   {tab === "themeSettings" ? <>
                     <div className="section-title"><SlidersHorizontal size={15} />通用主题设置</div>
-                    <div className="form-grid"><label><span>默认主题</span><select value={settings.default_theme} onChange={(event) => updateSettings("default_theme", event.target.value as Settings["default_theme"])}><option value="system">跟随系统</option><option value="light">浅色</option><option value="dark">深色</option></select></label><label><span>背景图地址</span><input type="text" value={settings.background_url} onChange={(event) => updateSettings("background_url", event.target.value)} /></label></div>
-                    <p className="settings-hint">背景图可用 | 分隔浅色和深色地址，例如 light.jpg | dark.jpg。</p>
+                    <div className="form-grid"><label><span>默认主题</span><select value={settings.default_theme} onChange={(event) => updateSettings("default_theme", event.target.value as Settings["default_theme"])}><option value="system">跟随系统</option><option value="light">浅色</option><option value="dark">深色</option></select></label><label><span>背景图地址</span><input type="text" maxLength={1000} value={settings.background_url} onChange={(event) => updateSettings("background_url", event.target.value)} placeholder="https://example.com/light.webp | https://example.com/dark.webp" /></label></div>
+                    <p className="settings-hint">仅支持 HTTPS 地址；浅色和深色背景可用 | 分隔。</p>
                     <div className="section-subtitle">当前主题选项</div><div className="theme-option-grid"><Toggle label="公开仪表盘" checked={settings.public_dashboard} onChange={(value) => updateSettings("public_dashboard", value)} />{themeSettingsSchema?.settings.map((field) => <ThemeOption key={field.key} field={field} value={settings.theme_options[field.key] ?? field.default} onChange={(value) => updateThemeOption(field.key, value)} />)}</div>
                     <div className="section-subtitle">公开界面元素</div>
                     <div className="settings-toggles"><Toggle label="显示搜索" checked={settings.show_search} onChange={(value) => updateSettings("show_search", value)} /><Toggle label="显示分组" checked={settings.show_groups} onChange={(value) => updateSettings("show_groups", value)} /><Toggle label="总览统计" checked={settings.show_stats} onChange={(value) => updateSettings("show_stats", value)} /><Toggle label="资产统计" checked={settings.show_assets} onChange={(value) => updateSettings("show_assets", value)} /><Toggle label="累计流量" checked={settings.show_traffic} onChange={(value) => updateSettings("show_traffic", value)} /><Toggle label="实时网速" checked={settings.show_speed} onChange={(value) => updateSettings("show_speed", value)} /><Toggle label="价格信息" checked={settings.show_price} onChange={(value) => updateSettings("show_price", value)} /><Toggle label="到期信息" checked={settings.show_expiry} onChange={(value) => updateSettings("show_expiry", value)} /><Toggle label="延迟与丢包" checked={settings.show_latency} onChange={(value) => updateSettings("show_latency", value)} /><Toggle label="在线时长" checked={settings.show_uptime} onChange={(value) => updateSettings("show_uptime", value)} /></div>
@@ -658,11 +663,11 @@ export function AdminPanel({
                     <p className="settings-hint">清空历史不会删除节点、密钥或最新状态。</p>
                   </> : null}
 
-                  {tab !== "data" && tab !== "about" ? <div className="form-actions"><button className="primary-btn" disabled={busy}><Save size={16} />保存{tab === "security" ? "账号与安全设置" : "设置"}</button></div> : null}
+                  {tab !== "data" ? <div className="form-actions"><button className="primary-btn" disabled={busy}><Save size={16} />保存{tab === "security" ? "账号与安全设置" : "设置"}</button></div> : null}
                 </form>
               ) : tab === "about" ? (
                 <div className="admin-section about-page">
-                  <div className="about-brand"><img src="/logo.svg" alt="" width="52" height="52" /><div><strong>NodeFlare</strong><small>基于 Rust、WebAssembly 和 Cloudflare Workers 的服务器监控</small></div></div>
+                  <div className="about-brand"><SiteLogo alt="" width="52" height="52" /><div><strong>NodeFlare</strong><small>基于 Rust、WebAssembly 和 Cloudflare Workers 的服务器监控</small></div></div>
                   <div className="about-rows">
                     <div className="about-row"><span>版本</span><strong>v{VERSION}</strong></div>
                     <div className="about-row"><span>项目地址</span><a href="https://github.com/imengying/NodeFlare" target="_blank" rel="noreferrer">github.com/imengying/NodeFlare<ExternalLink size={13} /></a></div>
@@ -674,8 +679,8 @@ export function AdminPanel({
           </div>
       </section>}
 
-      {editing ? <div className="submodal-backdrop" role="presentation" onMouseDown={() => setEditing(null)}><form className="editor-modal glass-panel" onSubmit={saveServer} onMouseDown={(event) => event.stopPropagation()}>
-        <header><div><span className="eyebrow">节点配置</span><h3>{editing === "new" ? "添加节点" : `编辑 · ${editing.name}`}</h3></div></header>
+      {editing ? <div className="submodal-backdrop" role="presentation" onMouseDown={serverDialog.onBackdropMouseDown}><form ref={serverDialog.dialogRef} className="editor-modal glass-panel" role="dialog" aria-modal="true" aria-labelledby="server-editor-title" tabIndex={-1} onSubmit={saveServer}>
+        <header><div><span className="eyebrow">节点配置</span><h3 id="server-editor-title">{editing === "new" ? "添加节点" : `编辑 · ${editing.name}`}</h3></div></header>
         <div className="form-grid"><label><span>名称</span><input autoFocus required value={form.name} onChange={(event) => updateForm("name", event.target.value)} /></label><label><span>地区代码</span><input maxLength={16} placeholder="CN / JP / DE" value={form.region} onChange={(event) => updateForm("region", event.target.value.toUpperCase())} /></label><label><span>分组</span><input value={form.group_name} onChange={(event) => updateForm("group_name", event.target.value)} /></label><label><span>标签</span><input placeholder="主力, 线路:BGP" value={form.tags} onChange={(event) => updateForm("tags", event.target.value)} /></label></div>
         <div className="form-grid three"><label><span>流量限额（GB）</span><input min="0" type="number" value={Math.round(form.traffic_limit / 1024 ** 3)} onChange={(event) => updateForm("traffic_limit", Number(event.target.value) * 1024 ** 3)} /></label><label><span>流量口径</span><select value={form.traffic_limit_type} onChange={(event) => updateForm("traffic_limit_type", event.target.value as ServerInput["traffic_limit_type"])}><option value="sum">上下行合计</option><option value="max">取较大值</option><option value="min">取较小值</option><option value="up">仅上行</option><option value="down">仅下行</option></select></label><label><span>流量重置日</span><input min="1" max="31" type="number" value={form.reset_day} onChange={(event) => updateForm("reset_day", Number(event.target.value))} /></label></div>
         <div className="form-grid three"><label><span>价格（0 隐藏，-1 免费）</span><input min="-1" step="0.01" type="number" value={form.price} onChange={(event) => updateForm("price", Number(event.target.value))} /></label><label><span>币种</span><select value={form.currency} onChange={(event) => updateForm("currency", event.target.value)}>{ASSET_CURRENCIES.map((code) => <option key={code}>{code}</option>)}</select></label><label><span>计费周期（天）</span><input min="1" max="3650" type="number" value={form.billing_cycle} onChange={(event) => updateForm("billing_cycle", Number(event.target.value))} /></label></div>
@@ -685,7 +690,7 @@ export function AdminPanel({
         <div className="form-actions"><button type="button" className="secondary-btn" onClick={() => setEditing(null)}>取消</button><button className="primary-btn" disabled={busy}><Save size={16} />保存节点</button></div>
       </form></div> : null}
 
-      {installCommand ? <div className="submodal-backdrop" role="presentation" onMouseDown={() => setInstall(null)}><section className="install-modal glass-panel" onMouseDown={(event) => event.stopPropagation()}><header><div><span className="eyebrow">Agent 部署</span><h3>安装命令</h3></div><div className="segmented install-platform" aria-label="Agent 平台"><button type="button" className={installPlatform === "linux" ? "active" : ""} onClick={() => setInstallPlatform("linux")}>Linux</button><button type="button" className={installPlatform === "windows" ? "active" : ""} onClick={() => setInstallPlatform("windows")}>Windows</button><button type="button" className={installPlatform === "macos" ? "active" : ""} onClick={() => setInstallPlatform("macos")}>macOS ARM</button></div></header><div className="install-list"><pre>{installCommand}</pre></div><div className="form-actions"><button className="secondary-btn" type="button" onClick={() => setInstall(null)}>关闭</button><button className="primary-btn" type="button" onClick={() => void copyInstallCommand()}><Copy size={16} />复制</button></div></section></div> : null}
+      {installCommand ? <div className="submodal-backdrop" role="presentation" onMouseDown={installDialog.onBackdropMouseDown}><section ref={installDialog.dialogRef} className="install-modal glass-panel" role="dialog" aria-modal="true" aria-labelledby="install-dialog-title" tabIndex={-1}><header><div><span className="eyebrow">Agent 部署</span><h3 id="install-dialog-title">安装命令</h3></div><div className="segmented install-platform" aria-label="Agent 平台"><button type="button" className={installPlatform === "linux" ? "active" : ""} onClick={() => setInstallPlatform("linux")}>Linux</button><button type="button" className={installPlatform === "windows" ? "active" : ""} onClick={() => setInstallPlatform("windows")}>Windows</button><button type="button" className={installPlatform === "macos" ? "active" : ""} onClick={() => setInstallPlatform("macos")}>macOS ARM</button></div></header><div className="install-list"><pre>{installCommand}</pre></div><div className="form-actions"><button className="secondary-btn" type="button" onClick={() => setInstall(null)}>关闭</button><button className="primary-btn" type="button" onClick={() => void copyInstallCommand()}><Copy size={16} />复制</button></div></section></div> : null}
     </div>
   );
 }
diff --git a/frontend/src/components/AlertRuleManager.tsx b/frontend/src/components/AlertRuleManager.tsx
index f190f50..879496c 100644
--- a/frontend/src/components/AlertRuleManager.tsx
+++ b/frontend/src/components/AlertRuleManager.tsx
@@ -3,6 +3,7 @@ import { useCallback, useEffect, useState } from "react";
 import { api } from "../api";
 import type { AdminServer, AlertRule, AlertRuleInput } from "../types";
 import { Checkbox } from "./Checkbox";
+import { useDialog } from "./useDialog";
 
 const emptyRule: AlertRuleInput = {
   name: "",
@@ -32,6 +33,7 @@ export function AlertRuleManager({ servers, onError, onNotice }: {
   const [form, setForm] = useState<AlertRuleInput>(emptyRule);
   const [allServers, setAllServers] = useState(true);
   const [busy, setBusy] = useState(false);
+  const editorDialog = useDialog<HTMLElement>(editing !== null, () => setEditing(null));
 
   const load = useCallback(async () => {
     try { setRules((await api.alertRules()).rules); }
@@ -103,8 +105,8 @@ export function AlertRuleManager({ servers, onError, onNotice }: {
       {!rules.length ? <div className="list-empty">尚未配置资源告警规则</div> : null}
     </div>
 
-    {editing ? <div className="submodal-backdrop" role="presentation" onMouseDown={() => setEditing(null)}><section className="alert-rule-editor glass-panel" onMouseDown={(event) => event.stopPropagation()}>
-      <header><div><span className="eyebrow">通知规则</span><h3>{editing === "new" ? "新建资源告警" : "编辑资源告警"}</h3></div></header>
+    {editing ? <div className="submodal-backdrop" role="presentation" onMouseDown={editorDialog.onBackdropMouseDown}><section ref={editorDialog.dialogRef} className="alert-rule-editor glass-panel" role="dialog" aria-modal="true" aria-labelledby="alert-rule-editor-title" tabIndex={-1}>
+      <header><div><span className="eyebrow">通知规则</span><h3 id="alert-rule-editor-title">{editing === "new" ? "新建资源告警" : "编辑资源告警"}</h3></div></header>
       <label><span>规则名称</span><input required maxLength={80} value={form.name} onChange={(event) => setForm((current) => ({ ...current, name: event.target.value }))} /></label>
       <div className="form-grid"><label><span>监控指标</span><select value={form.metric} onChange={(event) => setForm((current) => ({ ...current, metric: event.target.value as AlertRuleInput["metric"] }))}>{Object.entries(metricLabels).map(([value, label]) => <option value={value} key={value}>{label}</option>)}</select></label><label><span>阈值（{unit}）</span><input required type="number" min="0.01" max={unit === "%" ? 100 : 1000000} step="0.01" value={form.threshold} onChange={(event) => setForm((current) => ({ ...current, threshold: Number(event.target.value) }))} /></label></div>
       <div className="form-grid"><label><span>时间窗口（分钟）</span><input required type="number" min="1" max="1440" value={form.duration_minutes} onChange={(event) => setForm((current) => ({ ...current, duration_minutes: Number(event.target.value) }))} /></label><label><span>判断方式</span><select value={form.aggregation} onChange={(event) => setForm((current) => ({ ...current, aggregation: event.target.value as AlertRuleInput["aggregation"] }))}><option value="average">窗口平均值</option><option value="continuous">窗口内持续超限</option></select></label></div>
diff --git a/frontend/src/components/LatencyManager.tsx b/frontend/src/components/LatencyManager.tsx
index cf2f018..a2e1025 100644
--- a/frontend/src/components/LatencyManager.tsx
+++ b/frontend/src/components/LatencyManager.tsx
@@ -3,6 +3,7 @@ import { type FormEvent, useCallback, useEffect, useMemo, useState } from "react
 import { api } from "../api";
 import type { AdminServer, LatencyTask, LatencyTaskInput } from "../types";
 import { Checkbox } from "./Checkbox";
+import { useDialog } from "./useDialog";
 
 const emptyTask: LatencyTaskInput = {
   name: "",
@@ -48,6 +49,7 @@ export function LatencyManager({
   const [editing, setEditing] = useState<LatencyTask | "new" | null>(null);
   const [form, setForm] = useState<LatencyTaskInput>(emptyTask);
   const [query, setQuery] = useState("");
+  const editorDialog = useDialog<HTMLFormElement>(editing !== null, () => setEditing(null));
 
   const load = useCallback(async () => {
     setBusy(true);
@@ -148,8 +150,8 @@ export function LatencyManager({
       {busy && !tasks.length ? <div className="list-empty">正在读取延迟任务</div> : null}
     </div>
 
-    {editing ? <div className="submodal-backdrop" role="presentation" onMouseDown={() => setEditing(null)}><form className="latency-editor glass-panel" onSubmit={save} onMouseDown={(event) => event.stopPropagation()}>
-      <header><div><span className="eyebrow">延迟检测</span><h3>{editing === "new" ? "添加任务" : `编辑 · ${editing.name}`}</h3></div></header>
+    {editing ? <div className="submodal-backdrop" role="presentation" onMouseDown={editorDialog.onBackdropMouseDown}><form ref={editorDialog.dialogRef} className="latency-editor glass-panel" role="dialog" aria-modal="true" aria-labelledby="latency-editor-title" tabIndex={-1} onSubmit={save}>
+      <header><div><span className="eyebrow">延迟检测</span><h3 id="latency-editor-title">{editing === "new" ? "添加任务" : `编辑 · ${editing.name}`}</h3></div></header>
       <div className="form-grid"><label><span>名称</span><input autoFocus required maxLength={80} value={form.name} onChange={(event) => setForm((current) => ({ ...current, name: event.target.value }))} /></label><label><span>类型</span><div className="segmented task-type-control"><button type="button" className={form.task_type === "icmp" ? "active" : ""} onClick={() => setForm((current) => ({ ...current, task_type: "icmp", port: null }))}>ICMP</button><button type="button" className={form.task_type === "tcp" ? "active" : ""} onClick={() => setForm((current) => ({ ...current, task_type: "tcp", port: current.port ?? 80 }))}>TCP</button></div></label></div>
       <div className="form-grid"><label><span>节点</span><input required maxLength={50} value={form.target} onChange={(event) => setForm((current) => ({ ...current, target: event.target.value }))} placeholder={form.task_type === "tcp" ? "example.com" : "1.1.1.1"} /></label>{form.task_type === "tcp" ? <label><span>端口</span><input type="number" min="1" max="65535" required value={form.port ?? ""} onChange={(event) => setForm((current) => ({ ...current, port: event.target.value ? Number(event.target.value) : null }))} placeholder="80" /></label> : <div />}</div>
       <label><span>检测间隔（秒）</span><input type="number" min="30" max="3600" required value={form.interval_seconds} onChange={(event) => setForm((current) => ({ ...current, interval_seconds: Number(event.target.value) }))} /></label>
diff --git a/frontend/src/components/SiteLogo.tsx b/frontend/src/components/SiteLogo.tsx
new file mode 100644
index 0000000..0ea125f
--- /dev/null
+++ b/frontend/src/components/SiteLogo.tsx
@@ -0,0 +1,15 @@
+import { useState, type ImgHTMLAttributes } from "react";
+
+const DEFAULT_LOGO = "/logo.svg";
+
+interface SiteLogoProps extends Omit<ImgHTMLAttributes<HTMLImageElement>, "src"> {
+  src?: string;
+}
+
+export function SiteLogo({ src = "", ...props }: SiteLogoProps) {
+  const requested = src.trim() || DEFAULT_LOGO;
+  const [failedSource, setFailedSource] = useState("");
+  const resolved = failedSource === requested ? DEFAULT_LOGO : requested;
+
+  return <img {...props} src={resolved} onError={() => setFailedSource(requested)} />;
+}
diff --git a/frontend/src/components/TurnstileWidget.tsx b/frontend/src/components/TurnstileWidget.tsx
index c7689d2..fac58d9 100644
--- a/frontend/src/components/TurnstileWidget.tsx
+++ b/frontend/src/components/TurnstileWidget.tsx
@@ -34,12 +34,14 @@ function loadScript() {
 
 export function TurnstileWidget({
   siteKey,
+  action,
   theme,
   resetKey,
   onVerify,
   onError,
 }: {
   siteKey: string;
+  action: "admin-login" | "public-dashboard";
   theme: "light" | "dark";
   resetKey?: number;
   onVerify: (token: string) => void;
@@ -61,6 +63,7 @@ export function TurnstileWidget({
       target.current.replaceChildren();
       widgetId.current = window.turnstile.render(target.current, {
         sitekey: siteKey,
+        action,
         theme,
         size: "flexible",
         callback: (token: string) => {
@@ -79,7 +82,7 @@ export function TurnstileWidget({
       if (widgetId.current && window.turnstile) window.turnstile.remove(widgetId.current);
       widgetId.current = "";
     };
-  }, [siteKey, theme, resetKey]);
+  }, [action, siteKey, theme, resetKey]);
 
   const testing = siteKey.startsWith("1x00000000000000000000");
   return <div className={`turnstile-widget${verified ? " verified" : ""}${testing ? " testing" : ""}`} ref={target} />;
diff --git a/frontend/src/components/useDialog.ts b/frontend/src/components/useDialog.ts
new file mode 100644
index 0000000..142bfcb
--- /dev/null
+++ b/frontend/src/components/useDialog.ts
@@ -0,0 +1,74 @@
+import { type MouseEvent as ReactMouseEvent, useCallback, useEffect, useRef } from "react";
+
+const FOCUSABLE_SELECTOR = [
+  "a[href]",
+  "button:not([disabled])",
+  "input:not([disabled])",
+  "select:not([disabled])",
+  "textarea:not([disabled])",
+  '[tabindex]:not([tabindex="-1"])',
+].join(",");
+
+function focusableElements(container: HTMLElement) {
+  return Array.from(container.querySelectorAll<HTMLElement>(FOCUSABLE_SELECTOR))
+    .filter((element) => !element.hidden && element.getClientRects().length > 0);
+}
+
+export function useDialog<T extends HTMLElement>(open: boolean, onClose: () => void) {
+  const dialogRef = useRef<T>(null);
+  const closeRef = useRef(onClose);
+  closeRef.current = onClose;
+
+  useEffect(() => {
+    if (!open) return;
+    const dialog = dialogRef.current;
+    if (!dialog) return;
+    const dialogElement: HTMLElement = dialog;
+    const previousFocus = document.activeElement instanceof HTMLElement
+      ? document.activeElement
+      : null;
+    const focusFrame = window.requestAnimationFrame(() => {
+      const initial = dialogElement.querySelector<HTMLElement>("[autofocus]")
+        ?? focusableElements(dialogElement)[0]
+        ?? dialogElement;
+      initial.focus();
+    });
+
+    function handleKeyDown(event: KeyboardEvent) {
+      if (event.key === "Escape") {
+        event.preventDefault();
+        closeRef.current();
+        return;
+      }
+      if (event.key !== "Tab") return;
+      const focusable = focusableElements(dialogElement);
+      if (!focusable.length) {
+        event.preventDefault();
+        dialogElement.focus();
+        return;
+      }
+      const first = focusable[0];
+      const last = focusable[focusable.length - 1];
+      if (event.shiftKey && (document.activeElement === first || !dialogElement.contains(document.activeElement))) {
+        event.preventDefault();
+        last.focus();
+      } else if (!event.shiftKey && (document.activeElement === last || !dialogElement.contains(document.activeElement))) {
+        event.preventDefault();
+        first.focus();
+      }
+    }
+
+    document.addEventListener("keydown", handleKeyDown);
+    return () => {
+      window.cancelAnimationFrame(focusFrame);
+      document.removeEventListener("keydown", handleKeyDown);
+      if (previousFocus?.isConnected) previousFocus.focus();
+    };
+  }, [open]);
+
+  const onBackdropMouseDown = useCallback((event: ReactMouseEvent<HTMLDivElement>) => {
+    if (event.target === event.currentTarget) closeRef.current();
+  }, []);
+
+  return { dialogRef, onBackdropMouseDown };
+}
diff --git a/frontend/src/demo.ts b/frontend/src/demo.ts
index e13ee4e..6e645c5 100644
--- a/frontend/src/demo.ts
+++ b/frontend/src/demo.ts
@@ -4,6 +4,7 @@ export const demoConfig: Config = {
   site_name: "NodeFlare",
   site_description: "边缘节点与核心服务运行状态",
   site_announcement: "",
+  logo_url: "",
   favicon_url: "",
   locale: "zh-CN",
   public_dashboard: true,
diff --git a/frontend/src/styles/admin.css b/frontend/src/styles/admin.css
index 7ce3956..4ac072f 100644
--- a/frontend/src/styles/admin.css
+++ b/frontend/src/styles/admin.css
@@ -55,7 +55,7 @@
 .admin-login-theme:hover { background: var(--admin-hover); }
 
 .login-form { display: flex; width: min(410px, calc(100% - 32px)); align-items: stretch; flex-direction: column; gap: 16px; border: 1px solid var(--admin-border); border-radius: 8px; padding: 32px; background: var(--admin-surface); }
-.login-form img { width: 44px; height: 44px; align-self: center; margin-bottom: 8px; }
+.login-form img { width: 44px; height: 44px; align-self: center; margin-bottom: 8px; object-fit: contain; }
 .login-copy { text-align: center; }
 .login-copy h1 { margin: 0; color: var(--admin-text); font-size: 22px; }
 .login-copy p { margin: 5px 0 0; color: var(--admin-muted); font-size: 13px; }
@@ -68,7 +68,7 @@
 .admin-shell { display: grid; width: 100%; max-width: 100vw; height: 100dvh; min-width: 0; min-height: 0; overflow: hidden; border: 0; border-radius: 0; background: var(--admin-surface); grid-template-rows: 64px minmax(0, 1fr); }
 .admin-topbar { z-index: 2; display: flex; width: 100%; max-width: 100vw; min-width: 0; align-items: center; justify-content: space-between; gap: 24px; overflow: hidden; border-bottom: 1px solid var(--admin-border); padding: 0 24px; background: var(--admin-surface); }
 .admin-brand { display: flex; min-width: 0; align-items: center; gap: 10px; padding: 0; color: var(--admin-text); text-align: left; text-decoration: none; }
-.admin-brand img { width: 32px; height: 32px; flex: 0 0 auto; }
+.admin-brand img { width: 32px; height: 32px; flex: 0 0 auto; object-fit: contain; }
 .admin-brand strong { overflow: hidden; max-width: 320px; font-size: 18px; text-overflow: ellipsis; white-space: nowrap; }
 .admin-topbar-actions { display: flex; align-items: center; gap: 8px; }
 .admin-topbar-actions button { display: inline-flex; min-height: 36px; align-items: center; gap: 6px; border: 1px solid var(--admin-border); border-radius: 6px; padding: 0 11px; color: var(--admin-text); background: var(--admin-surface); font-size: 13px; font-weight: 600; }
diff --git a/frontend/src/styles/dashboard.css b/frontend/src/styles/dashboard.css
index a68e147..04f2271 100644
--- a/frontend/src/styles/dashboard.css
+++ b/frontend/src/styles/dashboard.css
@@ -106,6 +106,7 @@
 .error-band button { font-weight: 700; }
 .empty-state, .chart-loading { display: flex; min-height: 340px; align-items: center; justify-content: center; flex-direction: column; gap: 16px; color: var(--muted-foreground); font-size: 13px; }
 .verification-gate { display: flex; width: min(430px, 100%); min-height: 380px; align-items: center; justify-content: center; flex-direction: column; gap: 14px; margin: 12vh auto 0; border: 1px solid var(--border); border-radius: 8px; padding: 30px; background: var(--card); box-shadow: var(--shadow); text-align: center; }
+.verification-gate > img, .dashboard-login-gate > img { object-fit: contain; }
 .verification-gate h1 { margin: 0; font-size: 19px; }
 .verification-gate p { margin: 4px 0 0; color: var(--muted-foreground); font-size: 11px; }
 .dashboard-login-gate { display: flex; width: min(420px, 100%); align-items: center; flex-direction: column; gap: 16px; margin: 9vh auto 0; border-radius: 8px; padding: 28px; }
diff --git a/frontend/src/types.ts b/frontend/src/types.ts
index 71ae026..7fd8a3b 100644
--- a/frontend/src/types.ts
+++ b/frontend/src/types.ts
@@ -2,6 +2,7 @@ export interface Config {
   site_name: string;
   site_description: string;
   site_announcement: string;
+  logo_url: string;
   favicon_url: string;
   locale: "zh-CN" | "en";
   public_dashboard: boolean;
diff --git a/migrations/initial_01.sql b/migrations/initial_01.sql
index e4fa88b..790c80e 100644
--- a/migrations/initial_01.sql
+++ b/migrations/initial_01.sql
@@ -113,6 +113,7 @@ INSERT INTO settings(id, value, updated_at) VALUES (
     '{
       "site_description": "轻量、实时的服务器运行状态",
       "site_announcement": "",
+      "logo_url": "",
       "favicon_url": "",
       "locale": "zh-CN",
       "public_dashboard": "true",
diff --git a/package.json b/package.json
index 1faee20..36fc5e4 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,8 @@
     "test:smoke": "sh scripts/smoke-test.sh"
   },
   "devDependencies": {
-    "wrangler": "^4.123.0"
+    "wrangler": "^4.123.0",
+    "ws": "^8.21.0"
   },
   "overrides": {
     "nanoid": "3.3.18"
diff --git a/scripts/build-frontend.sh b/scripts/build-frontend.sh
index a77e2bd..677f7a9 100644
--- a/scripts/build-frontend.sh
+++ b/scripts/build-frontend.sh
@@ -5,7 +5,7 @@ script_dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
 root_dir=$(CDPATH= cd -- "$script_dir/.." && pwd)
 NODEFLARE_VERSION=$(sh "$script_dir/resolve-version.sh")
 VITE_NODEFLARE_VERSION=$NODEFLARE_VERSION
-export NODEFLARE_VERSION VITE_NODEFLARE_VERSION
+export VITE_NODEFLARE_VERSION
 cd "$root_dir"
 
 bun run --cwd frontend build
diff --git a/scripts/build-worker.sh b/scripts/build-worker.sh
index d8b44d5..0dd9ce0 100644
--- a/scripts/build-worker.sh
+++ b/scripts/build-worker.sh
@@ -4,8 +4,7 @@ set -eu
 script_dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
 root_dir=$(CDPATH= cd -- "$script_dir/.." && pwd)
 NODEFLARE_VERSION=$(sh "$script_dir/resolve-version.sh")
-VITE_NODEFLARE_VERSION=$NODEFLARE_VERSION
-export NODEFLARE_VERSION VITE_NODEFLARE_VERSION
+export NODEFLARE_VERSION
 cd "$root_dir"
 
 current_build_key=$(sh scripts/build-key.sh worker 2>/dev/null || true)
diff --git a/scripts/resolve-version.sh b/scripts/resolve-version.sh
index a936c7d..650b047 100755
--- a/scripts/resolve-version.sh
+++ b/scripts/resolve-version.sh
@@ -11,6 +11,17 @@ fi
 if [ -z "$raw" ]; then
   raw=$(git -C "$root_dir" describe --tags --abbrev=0 --match 'v[0-9]*.[0-9]*.[0-9]*' 2>/dev/null || true)
 fi
+if [ -z "$raw" ]; then
+  remote_version=$(
+    git -C "$root_dir" ls-remote --tags --refs origin \
+      'refs/tags/v[0-9]*.[0-9]*.[0-9]*' 2>/dev/null |
+      awk '{ sub(/^refs\/tags\//, "", $2); print $2 }' |
+      grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$' |
+      sort -V |
+      tail -n 1
+  ) || remote_version=
+  raw=$remote_version
+fi
 if [ -z "$raw" ]; then
   raw=$(sed -n 's/^[[:space:]]*"version": "\([^"]*\)",*$/\1/p' "$root_dir/package.json" | sed -n '1p')
 fi
diff --git a/scripts/smoke-test.sh b/scripts/smoke-test.sh
index 6fb430e..f684192 100644
--- a/scripts/smoke-test.sh
+++ b/scripts/smoke-test.sh
@@ -109,6 +109,8 @@ server_json=$(request -H "Authorization: Bearer $admin_token" \
   "$MONITOR_BASE_URL/api/admin/servers")
 server_id=$(printf '%s' "$server_json" | jq -er '.id')
 agent_token=$(printf '%s' "$server_json" | jq -er '.agent_token')
+MONITOR_BASE_URL="$MONITOR_BASE_URL" MONITOR_ADMIN_TOKEN="$admin_token" \
+  MONITOR_AGENT_TOKEN="$agent_token" node scripts/websocket-smoke.mjs
 token_without_admin_status=$(monitor_curl --silent --output /dev/null --write-out '%{http_code}' \
   "$MONITOR_BASE_URL/api/admin/servers/$server_id/token")
 [ "$token_without_admin_status" = "401" ]
diff --git a/scripts/websocket-smoke.mjs b/scripts/websocket-smoke.mjs
new file mode 100644
index 0000000..d8e1475
--- /dev/null
+++ b/scripts/websocket-smoke.mjs
@@ -0,0 +1,82 @@
+import WebSocket from "ws";
+
+const baseUrl = process.env.MONITOR_BASE_URL;
+const adminToken = process.env.MONITOR_ADMIN_TOKEN;
+const agentToken = process.env.MONITOR_AGENT_TOKEN;
+
+if (!baseUrl || !adminToken || !agentToken) {
+  throw new Error("MONITOR_BASE_URL, MONITOR_ADMIN_TOKEN and MONITOR_AGENT_TOKEN are required");
+}
+
+function websocketUrl(path) {
+  const url = new URL(path, baseUrl);
+  url.protocol = url.protocol === "https:" ? "wss:" : "ws:";
+  return url.toString();
+}
+
+function openSocket(path, token) {
+  return new Promise((resolve, reject) => {
+    const socket = new WebSocket(websocketUrl(path), {
+      headers: { Authorization: `Bearer ${token}` },
+    });
+    const timer = setTimeout(() => {
+      socket.terminate();
+      reject(new Error(`${path} WebSocket handshake timed out`));
+    }, 5_000);
+    socket.once("open", () => {
+      clearTimeout(timer);
+      resolve(socket);
+    });
+    socket.once("unexpected-response", (_request, response) => {
+      clearTimeout(timer);
+      reject(new Error(`${path} WebSocket returned HTTP ${response.statusCode}`));
+    });
+    socket.once("error", (error) => {
+      clearTimeout(timer);
+      reject(error);
+    });
+  });
+}
+
+function waitForMessage(socket, expected) {
+  return new Promise((resolve, reject) => {
+    const timer = setTimeout(() => reject(new Error(`WebSocket did not receive ${expected}`)), 5_000);
+    socket.once("message", (data) => {
+      clearTimeout(timer);
+      const message = data.toString();
+      if (message !== expected) reject(new Error(`Expected ${expected}, received ${message}`));
+      else resolve();
+    });
+    socket.once("error", (error) => {
+      clearTimeout(timer);
+      reject(error);
+    });
+  });
+}
+
+function closeSocket(socket) {
+  return new Promise((resolve, reject) => {
+    const timer = setTimeout(() => {
+      socket.terminate();
+      reject(new Error("WebSocket close timed out"));
+    }, 5_000);
+    socket.once("close", () => {
+      clearTimeout(timer);
+      resolve();
+    });
+    socket.once("error", (error) => {
+      clearTimeout(timer);
+      reject(error);
+    });
+    socket.close();
+  });
+}
+
+const dashboard = await openSocket("/api/ws", adminToken);
+const pong = waitForMessage(dashboard, "pong");
+dashboard.send("ping");
+await pong;
+await closeSocket(dashboard);
+
+const agent = await openSocket("/api/agent/live", agentToken);
+await closeSocket(agent);
diff --git a/src/db.rs b/src/db.rs
index 5af9635..cae02ba 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -1,4 +1,3 @@
-use std::cell::RefCell;
 use std::collections::HashMap;
 
 use serde::{Deserialize, Serialize, Serializer};
@@ -71,30 +70,6 @@ FROM servers s
 LEFT JOIN latest_state m ON m.server_id = s.id
 "#;
 
-const SETTINGS_CACHE_TTL_SECONDS: i64 = 30;
-
-#[derive(Clone, PartialEq)]
-struct SettingsCacheKey {
-    default_name: String,
-    default_threshold: i64,
-    default_retention: i64,
-    default_username: String,
-}
-
-struct SettingsCacheEntry {
-    key: SettingsCacheKey,
-    expires_at: i64,
-    settings: SettingsView,
-}
-
-thread_local! {
-    static SETTINGS_CACHE: RefCell<Option<SettingsCacheEntry>> = const { RefCell::new(None) };
-}
-
-fn invalidate_settings_cache() {
-    SETTINGS_CACHE.with(|cache| *cache.borrow_mut() = None);
-}
-
 pub const SECRET_MASK: &str = "********";
 
 fn secret_for_api(value: &str) -> &str {
@@ -347,6 +322,7 @@ pub struct SettingsView {
     pub site_name: String,
     pub site_description: String,
     pub site_announcement: String,
+    pub logo_url: String,
     pub favicon_url: String,
     pub locale: String,
     pub public_dashboard: bool,
@@ -1299,22 +1275,6 @@ pub async fn settings(
     default_retention: i64,
     default_username: &str,
 ) -> Result<SettingsView> {
-    let cache_key = SettingsCacheKey {
-        default_name: default_name.to_string(),
-        default_threshold,
-        default_retention,
-        default_username: default_username.to_string(),
-    };
-    let current = now();
-    if let Some(settings) = SETTINGS_CACHE.with(|cache| {
-        cache
-            .borrow()
-            .as_ref()
-            .filter(|entry| entry.key == cache_key && entry.expires_at > current)
-            .map(|entry| entry.settings.clone())
-    }) {
-        return Ok(settings);
-    }
     let raw = db
         .prepare("SELECT value FROM settings WHERE id = 1")
         .first::<String>(Some("value"))
@@ -1322,13 +1282,14 @@ pub async fn settings(
         .ok_or_else(|| worker::Error::RustError("站点设置尚未初始化".to_string()))?;
     let values: HashMap<String, String> = serde_json::from_str(&raw)
         .map_err(|_| worker::Error::RustError("站点设置格式无效".to_string()))?;
-    let settings = SettingsView {
+    Ok(SettingsView {
         site_name: values
             .get("site_name")
             .cloned()
             .unwrap_or_else(|| default_name.to_string()),
         site_description: string_setting(&values, "site_description", "轻量、实时的服务器运行状态"),
         site_announcement: string_setting(&values, "site_announcement", ""),
+        logo_url: string_setting(&values, "logo_url", ""),
         favicon_url: string_setting(&values, "favicon_url", ""),
         locale: string_setting(&values, "locale", "zh-CN"),
         public_dashboard: bool_setting(&values, "public_dashboard", true),
@@ -1377,15 +1338,7 @@ pub async fn settings(
         expiry_alert_days: integer_setting(&values, "expiry_alert_days", 7),
         cloudflare_account_id: string_setting(&values, "cloudflare_account_id", ""),
         cloudflare_api_token: string_setting(&values, "cloudflare_api_token", ""),
-    };
-    SETTINGS_CACHE.with(|cache| {
-        *cache.borrow_mut() = Some(SettingsCacheEntry {
-            key: cache_key,
-            expires_at: current + SETTINGS_CACHE_TTL_SECONDS,
-            settings: settings.clone(),
-        });
-    });
-    Ok(settings)
+    })
 }
 
 pub async fn update_settings(
@@ -1409,6 +1362,9 @@ pub async fn update_settings(
     if let Some(value) = input.site_announcement.as_deref() {
         push_setting!("site_announcement", value.trim());
     }
+    if let Some(value) = input.logo_url.as_deref() {
+        push_setting!("logo_url", value.trim());
+    }
     if let Some(value) = input.favicon_url.as_deref() {
         push_setting!("favicon_url", value.trim());
     }
@@ -1545,7 +1501,6 @@ pub async fn update_settings(
             ])?
             .run()
             .await?;
-        invalidate_settings_cache();
     }
     Ok(())
 }
@@ -1894,7 +1849,6 @@ pub async fn save_setting(db: &D1Database, key: &str, value: &str) -> Result<()>
         .bind(&[text(&format!("$.{key}")), text(value), number(now())])?
         .run()
         .await?;
-    invalidate_settings_cache();
     Ok(())
 }
 
@@ -1907,7 +1861,6 @@ pub async fn increment_setting(db: &D1Database, key: &str) -> Result<()> {
     .bind(&[text(&format!("$.{key}")), number(now())])?
     .run()
     .await?;
-    invalidate_settings_cache();
     Ok(())
 }
 
@@ -1922,12 +1875,10 @@ pub async fn update_expiry(db: &D1Database, id: &str, expires_at: i64) -> Result
 #[cfg(test)]
 mod tests {
     use super::{
-        alert_window_covered, history_cutoffs, non_empty_string_setting, secret_for_api,
-        traffic_cycle_key, AlertMetricRow, HistoryMetricAggregate, TrafficCounterState,
-        SECRET_MASK,
+        alert_window_covered, secret_for_api, traffic_cycle_key, AlertMetricRow,
+        HistoryMetricAggregate, TrafficCounterState, SECRET_MASK,
     };
     use crate::models::AgentReport;
-    use std::collections::HashMap;
 
     fn row(samples: i64, last_timestamp: i64, report_interval: i64) -> AlertMetricRow {
         AlertMetricRow {
@@ -1968,33 +1919,6 @@ mod tests {
         assert_eq!(secret_for_api("stored-secret"), SECRET_MASK);
     }
 
-    #[test]
-    fn requires_an_explicit_admin_username() {
-        let mut values = HashMap::from([("admin_username".to_string(), String::new())]);
-        assert_eq!(
-            non_empty_string_setting(&values, "admin_username", "operator"),
-            "operator"
-        );
-        assert_eq!(non_empty_string_setting(&values, "admin_username", ""), "");
-        values.insert("admin_username".to_string(), "owner".to_string());
-        assert_eq!(
-            non_empty_string_setting(&values, "admin_username", "operator"),
-            "owner"
-        );
-    }
-
-    #[test]
-    fn honors_short_and_long_history_retention() {
-        let current = 10_000_000;
-        let (one_day, one_day_recent) = history_cutoffs(current, 1);
-        assert_eq!(one_day, current - 86_400);
-        assert_eq!(one_day_recent, one_day);
-
-        let (thirty_days, thirty_days_recent) = history_cutoffs(current, 30);
-        assert_eq!(thirty_days, current - 30 * 86_400);
-        assert_eq!(thirty_days_recent, current - 86_400);
-    }
-
     #[test]
     fn assigns_monthly_traffic_periods_with_short_months() {
         let timestamp = |year: i64, month: i64, day: i64| {
@@ -2141,26 +2065,4 @@ mod tests {
         assert_eq!(point.net_rx_total, 2_000);
         assert_eq!(point.net_tx_total, 3_000);
     }
-
-    #[test]
-    fn excludes_reports_already_persisted() {
-        let reports = [
-            AgentReport {
-                timestamp: 99,
-                ..AgentReport::default()
-            },
-            AgentReport {
-                timestamp: 100,
-                ..AgentReport::default()
-            },
-            AgentReport {
-                timestamp: 101,
-                ..AgentReport::default()
-            },
-        ];
-
-        let fresh = super::reports_after(&reports, 100);
-        assert_eq!(fresh.len(), 1);
-        assert_eq!(fresh[0].timestamp, 101);
-    }
 }
diff --git a/src/exchange.rs b/src/exchange.rs
index e370077..073c2d4 100644
--- a/src/exchange.rs
+++ b/src/exchange.rs
@@ -2,7 +2,9 @@ use std::{collections::BTreeMap, time::Duration};
 
 use serde::Serialize;
 use serde_json::Value;
-use worker::{AbortController, D1Database, Error, Fetch, Method, Request, Result};
+use worker::{D1Database, Error, Method, Request, Result};
+
+use crate::outbound::fetch_with_timeout;
 
 use crate::{cloudflare, db};
 
@@ -136,13 +138,11 @@ async fn fetch_json(url: &str) -> Result<Value> {
     request
         .headers()
         .set("User-Agent", "NodeFlare-Exchange-Rates")?;
-    let controller = AbortController::default();
-    let signal = controller.signal();
-    worker::wasm_bindgen_futures::spawn_local(async move {
-        worker::Delay::from(Duration::from_secs(8)).await;
-        controller.abort();
-    });
-    let mut response = Fetch::Request(request).send_with_signal(&signal).await?;
+    let Some(mut response) = fetch_with_timeout(request, Duration::from_secs(8)).await? else {
+        return Err(Error::RustError(
+            "exchange-rate upstream request timed out".to_string(),
+        ));
+    };
     let status = response.status_code();
     if !(200..300).contains(&status) {
         return Err(Error::RustError(format!(
@@ -246,7 +246,7 @@ pub async fn refresh(
 
 #[cfg(test)]
 mod tests {
-    use super::{default_rates, due, parse_er_api, parse_frankfurter};
+    use super::{default_rates, parse_er_api, parse_frankfurter};
 
     #[test]
     fn provides_all_frontend_asset_currencies() {
@@ -307,14 +307,4 @@ mod tests {
         });
         assert!(parse_frankfurter(&wrong_base).is_none());
     }
-
-    #[test]
-    fn refreshes_daily_and_retries_hourly() {
-        let current = 200_000;
-        assert!(due(0, 0, current, false));
-        assert!(!due(current - 10, 0, current, false));
-        assert!(!due(0, current - 10, current, false));
-        assert!(due(current - 86_400, current - 3_600, current, false));
-        assert!(due(current, current, current, true));
-    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index d40ab3a..20f4b7a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,6 +6,7 @@ mod latency;
 mod live;
 mod models;
 mod notify;
+mod outbound;
 mod routes;
 mod theme;
 mod turnstile;
@@ -18,7 +19,7 @@ use serde::{de::DeserializeOwned, Serialize};
 use worker::*;
 
 use crate::auth::{
-    bearer_token, is_admin, sha256_hex, verify_turnstile_proof, ADMIN_SESSION_SECONDS,
+    bearer_token, is_admin, random_salt, sha256_hex, verify_turnstile_proof, ADMIN_SESSION_SECONDS,
 };
 use crate::models::{
     AgentDiskMetric, AgentGpuMetric, AgentReport, AlertRuleInput, ApiError, LatencyTaskInput,
@@ -205,7 +206,35 @@ async fn request_json<T: DeserializeOwned>(req: &mut Request, limit: usize) -> R
 }
 
 pub(crate) fn error(message: &str, status: u16) -> Result<Response> {
-    json(&ApiError { error: message }, status)
+    json(
+        &ApiError {
+            error: message,
+            request_id: None,
+        },
+        status,
+    )
+}
+
+fn internal_error(request_id: &str) -> Result<Response> {
+    let mut response = json(
+        &ApiError {
+            error: "服务暂时不可用，请稍后重试",
+            request_id: Some(request_id),
+        },
+        500,
+    )?;
+    response.headers_mut().set("X-Request-Id", request_id)?;
+    Ok(response)
+}
+
+fn request_id(req: &Request) -> String {
+    req.headers()
+        .get("CF-Ray")
+        .ok()
+        .flatten()
+        .filter(|value| !value.trim().is_empty())
+        .or_else(random_salt)
+        .unwrap_or_else(|| format!("local-{}", Date::now().as_millis() as i64))
 }
 
 fn rate_limited() -> Result<Response> {
@@ -492,6 +521,38 @@ pub(crate) fn valid_password_derived(value: &str) -> bool {
             .all(|byte| byte.is_ascii_digit() || matches!(byte, b'a'..=b'f'))
 }
 
+pub(crate) fn valid_public_asset_url(value: &str) -> bool {
+    let value = value.trim();
+    if value.is_empty() {
+        return true;
+    }
+    if value.chars().count() > 1000 {
+        return false;
+    }
+    Url::parse(value).is_ok_and(|url| {
+        url.scheme() == "https"
+            && url.host_str().is_some_and(|host| !host.is_empty())
+            && url.username().is_empty()
+            && url.password().is_none()
+    })
+}
+
+pub(crate) fn valid_background_urls(value: &str) -> bool {
+    let value = value.trim();
+    if value.is_empty() {
+        return true;
+    }
+    if value.chars().count() > 1000 {
+        return false;
+    }
+    let parts = value.split('|').collect::<Vec<_>>();
+    parts.len() <= 2
+        && parts.iter().any(|part| !part.trim().is_empty())
+        && parts
+            .iter()
+            .all(|part| part.trim().is_empty() || valid_public_asset_url(part))
+}
+
 fn valid_server_price(value: f64) -> bool {
     value.is_finite() && (-1.0..=1_000_000_000.0).contains(&value)
 }
@@ -1106,7 +1167,9 @@ async fn handle(req: Request, env: Env, ctx: Context) -> Result<Response> {
 #[event(fetch, respond_with_errors)]
 async fn fetch(req: Request, env: Env, ctx: Context) -> Result<Response> {
     let method = req.method();
+    let method_name = format!("{method:?}");
     let path = req.path();
+    let request_id = request_id(&req);
     let request_url = req.url().ok();
     let origin = req.headers().get("Origin").ok().flatten();
 
@@ -1133,8 +1196,17 @@ async fn fetch(req: Request, env: Env, ctx: Context) -> Result<Response> {
     match handle(req, env, ctx).await {
         Ok(response) => Ok(response),
         Err(err) => {
-            console_error!("request failed: {err}");
-            error("服务暂时不可用，请检查 D1 迁移与绑定", 500)
+            console_error!(
+                "{}",
+                serde_json::json!({
+                    "event": "request_failed",
+                    "request_id": request_id,
+                    "method": method_name,
+                    "path": path,
+                    "error": err.to_string(),
+                })
+            );
+            internal_error(&request_id)
         }
     }
 }
@@ -1198,9 +1270,9 @@ mod tests {
     use super::{
         allow_on_rate_limit_failure, history_cache_key, history_cache_seconds, rate_limit_binding,
         rewrite_remote_theme_index, same_origin, submitted_secret, valid_agent_mirror,
-        valid_cloudflare_account_id, valid_cloudflare_api_token, valid_password_derived,
-        valid_ping_target, valid_server_price, validate_latency_task, validate_server, ADMIN_HTML,
-        ADMIN_SCRIPT, ADMIN_STYLE,
+        valid_background_urls, valid_cloudflare_account_id, valid_cloudflare_api_token,
+        valid_password_derived, valid_ping_target, valid_public_asset_url, validate_latency_task,
+        validate_server,
     };
     use crate::{db::SECRET_MASK, models::LatencyTaskInput, models::ServerInput};
     use worker::{Method, Url};
@@ -1248,15 +1320,6 @@ mod tests {
         assert_eq!(history_cache_seconds(120), 600);
     }
 
-    #[test]
-    fn validates_server_prices() {
-        assert!(valid_server_price(-1.0));
-        assert!(valid_server_price(0.0));
-        assert!(valid_server_price(1_000_000_000.0));
-        assert!(!valid_server_price(-1.01));
-        assert!(!valid_server_price(f64::NAN));
-    }
-
     #[test]
     fn bounds_samples_buffered_between_reports() {
         let mut server = ServerInput {
@@ -1410,13 +1473,31 @@ mod tests {
     }
 
     #[test]
-    fn embeds_the_admin_frontend() {
-        assert!(ADMIN_HTML.starts_with(b"<!doctype html>"));
-        assert!(ADMIN_HTML
-            .windows(b"/admin-assets/admin.js".len())
-            .any(|value| value == b"/admin-assets/admin.js"));
-        assert!(!ADMIN_SCRIPT.is_empty());
-        assert!(!ADMIN_STYLE.is_empty());
+    fn validates_public_asset_urls() {
+        assert!(valid_public_asset_url(""));
+        assert!(valid_public_asset_url("https://cdn.example.com/logo.svg"));
+        assert!(valid_public_asset_url(
+            "https://cdn.example.com/background.webp?size=large#hero"
+        ));
+        assert!(!valid_public_asset_url("http://cdn.example.com/logo.svg"));
+        assert!(!valid_public_asset_url("/logo.svg"));
+        assert!(!valid_public_asset_url(
+            "https://user:pass@example.com/logo.svg"
+        ));
+
+        assert!(valid_background_urls(""));
+        assert!(valid_background_urls(
+            "https://cdn.example.com/light.webp | https://cdn.example.com/dark.webp"
+        ));
+        assert!(valid_background_urls(
+            "https://cdn.example.com/light.webp |"
+        ));
+        assert!(valid_background_urls("| https://cdn.example.com/dark.webp"));
+        assert!(!valid_background_urls("|"));
+        assert!(!valid_background_urls(
+            "https://cdn.example.com/a.webp | https://cdn.example.com/b.webp | https://cdn.example.com/c.webp"
+        ));
+        assert!(!valid_background_urls("javascript:alert(1)"));
     }
 
     #[test]
diff --git a/src/live.rs b/src/live.rs
index 980e152..0e45ba0 100644
--- a/src/live.rs
+++ b/src/live.rs
@@ -1016,7 +1016,10 @@ impl DurableObject for LiveHub {
         reason: String,
         _was_clean: bool,
     ) -> Result<()> {
-        ws.close(Some(code as u16), Some(reason))
+        match outbound_close_code(code) {
+            Some(code) => ws.close(Some(code), Some(reason)),
+            None => ws.close(None, None::<&str>),
+        }
     }
 
     async fn websocket_error(&self, ws: WebSocket, _error: Error) -> Result<()> {
@@ -1024,6 +1027,11 @@ impl DurableObject for LiveHub {
     }
 }
 
+fn outbound_close_code(code: usize) -> Option<u16> {
+    let code = u16::try_from(code).ok()?;
+    ((1000..=4999).contains(&code) && !matches!(code, 1004..=1006 | 1015)).then_some(code)
+}
+
 async fn post_live_action(env: &Env, path: &str, action: &str, body: &str) -> Result<Response> {
     let namespace = env.durable_object("LIVE_HUB")?;
     let stub = namespace.id_from_name("dashboard")?.get_stub()?;
@@ -1126,6 +1134,7 @@ pub async fn disconnect_agents(env: &Env, server_ids: &[String]) -> Result<()> {
 pub async fn upgrade(req: Request, env: &Env) -> Result<Response> {
     let namespace = env.durable_object("LIVE_HUB")?;
     let stub = namespace.id_from_name("dashboard")?.get_stub()?;
+    let req = req.clone_mut()?;
     req.headers().delete("X-Live-Agent-ID")?;
     req.headers().delete("X-Live-Agent-Hidden")?;
     for header in [
@@ -1157,6 +1166,7 @@ pub async fn upgrade_agent(
 ) -> Result<Response> {
     let namespace = env.durable_object("LIVE_HUB")?;
     let stub = namespace.id_from_name("dashboard")?.get_stub()?;
+    let req = req.clone_mut()?;
     req.headers().set("X-Live-Agent-ID", server_id)?;
     req.headers()
         .set("X-Live-Agent-Hidden", if hidden { "1" } else { "0" })?;
@@ -1204,11 +1214,11 @@ pub async fn upgrade_agent(
 mod tests {
     use super::{
         agent_wss_interval_ms, batch_update_parts_at, begin_d1_flush, cached_update_value,
-        finish_d1_flush, live_ack_payload, next_d1_write_ms, trim_cached_live_samples,
-        trim_socket_attachment, update_alert_window, AlertEvaluationServer, AlertWindowSample,
-        CachedLiveSample, SocketAttachment, TrafficAttachment, ALERT_WINDOW_SECONDS,
-        CACHED_LIVE_TTL_SECONDS, MAX_CACHED_LIVE_BYTES, MAX_CACHED_LIVE_SAMPLES,
-        MAX_SERIALIZED_ATTACHMENT_BYTES,
+        finish_d1_flush, live_ack_payload, next_d1_write_ms, outbound_close_code,
+        trim_cached_live_samples, trim_socket_attachment, update_alert_window,
+        AlertEvaluationServer, AlertWindowSample, CachedLiveSample, SocketAttachment,
+        TrafficAttachment, ALERT_WINDOW_SECONDS, CACHED_LIVE_TTL_SECONDS, MAX_CACHED_LIVE_BYTES,
+        MAX_CACHED_LIVE_SAMPLES, MAX_SERIALIZED_ATTACHMENT_BYTES,
     };
     use crate::db::HistoryMetricAggregate;
     use crate::latency::LatencyMetricAggregates;
@@ -1228,6 +1238,19 @@ mod tests {
         }
     }
 
+    #[test]
+    fn filters_reserved_and_invalid_websocket_close_codes() {
+        assert_eq!(outbound_close_code(1000), Some(1000));
+        assert_eq!(outbound_close_code(1011), Some(1011));
+        assert_eq!(outbound_close_code(4000), Some(4000));
+        assert_eq!(outbound_close_code(999), None);
+        assert_eq!(outbound_close_code(1004), None);
+        assert_eq!(outbound_close_code(1005), None);
+        assert_eq!(outbound_close_code(1006), None);
+        assert_eq!(outbound_close_code(1015), None);
+        assert_eq!(outbound_close_code(5000), None);
+    }
+
     #[test]
     fn live_payload_contains_cycle_adjusted_traffic_and_latency() {
         let report = AgentReport {
diff --git a/src/models.rs b/src/models.rs
index b4195a1..1f157dd 100644
--- a/src/models.rs
+++ b/src/models.rs
@@ -54,6 +54,7 @@ pub struct SettingsInput {
     pub site_name: Option<String>,
     pub site_description: Option<String>,
     pub site_announcement: Option<String>,
+    pub logo_url: Option<String>,
     pub favicon_url: Option<String>,
     pub locale: Option<String>,
     pub public_dashboard: Option<bool>,
@@ -366,4 +367,6 @@ pub struct AlertRuleView {
 #[derive(Debug, Serialize)]
 pub struct ApiError<'a> {
     pub error: &'a str,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub request_id: Option<&'a str>,
 }
diff --git a/src/outbound.rs b/src/outbound.rs
new file mode 100644
index 0000000..ed22a34
--- /dev/null
+++ b/src/outbound.rs
@@ -0,0 +1,21 @@
+use std::time::Duration;
+
+use futures_util::{future::select, pin_mut};
+use worker::{AbortController, Delay, Fetch, Request, Response, Result};
+
+pub async fn fetch_with_timeout(request: Request, timeout: Duration) -> Result<Option<Response>> {
+    let controller = AbortController::default();
+    let signal = controller.signal();
+    let fetch_request = Fetch::Request(request);
+    let fetch = fetch_request.send_with_signal(&signal);
+    let delay = Delay::from(timeout);
+    pin_mut!(fetch, delay);
+
+    match select(fetch, delay).await {
+        futures_util::future::Either::Left((response, _)) => response.map(Some),
+        futures_util::future::Either::Right(((), _)) => {
+            controller.abort();
+            Ok(None)
+        }
+    }
+}
diff --git a/src/routes/admin.rs b/src/routes/admin.rs
index 75a793b..4246947 100644
--- a/src/routes/admin.rs
+++ b/src/routes/admin.rs
@@ -1,6 +1,6 @@
 use std::collections::HashSet;
 
-use worker::{console_error, console_warn, Method, Request, Response, Result, Url};
+use worker::{console_error, console_warn, Method, Request, Response, Result};
 
 use crate::auth::{
     create_admin_jwt, create_theme_preview_proof, hash_password, random_salt, sha256_hex,
@@ -11,9 +11,10 @@ use crate::models::{
 };
 use crate::routes::{RouteContext, RouteOutcome};
 use crate::{
-    cloudflare, db, error, exchange, json, latency, live, no_content, notify, now, request_json,
-    server_id, settings_for_admin_response, submitted_secret, theme, valid_cloudflare_account_id,
-    valid_cloudflare_api_token, valid_password_derived, validate_alert_rule, validate_latency_task,
+    cloudflare, db, env_secret_text, error, exchange, json, latency, live, no_content, notify, now,
+    request_json, server_id, settings_for_admin_response, submitted_secret, theme,
+    valid_background_urls, valid_cloudflare_account_id, valid_cloudflare_api_token,
+    valid_password_derived, valid_public_asset_url, validate_alert_rule, validate_latency_task,
     validate_server, validate_theme, API_JSON_MAX_BYTES,
 };
 
@@ -555,20 +556,12 @@ async fn exchange_rates_refresh(ctx: &RouteContext) -> Result<Response> {
 
 async fn cloudflare_usage(ctx: &RouteContext) -> Result<Response> {
     let account_id = if ctx.settings.cloudflare_account_id.trim().is_empty() {
-        ctx.env
-            .secret("CF_USAGE_ACCOUNT_ID")
-            .or_else(|_| ctx.env.var("CF_USAGE_ACCOUNT_ID"))
-            .map(|value| value.to_string())
-            .unwrap_or_default()
+        env_secret_text(&ctx.env, "CF_USAGE_ACCOUNT_ID")
     } else {
         ctx.settings.cloudflare_account_id.clone()
     };
     let token = if ctx.settings.cloudflare_api_token.trim().is_empty() {
-        ctx.env
-            .secret("CF_USAGE_API_TOKEN")
-            .or_else(|_| ctx.env.var("CF_USAGE_API_TOKEN"))
-            .map(|value| value.to_string())
-            .unwrap_or_default()
+        env_secret_text(&ctx.env, "CF_USAGE_API_TOKEN")
     } else {
         ctx.settings.cloudflare_api_token.clone()
     };
@@ -624,6 +617,13 @@ async fn settings_patch(req: &mut Request, ctx: &RouteContext) -> Result<Respons
     {
         return error("站点公告不能超过 1000 个字符", 400);
     }
+    if input
+        .logo_url
+        .as_deref()
+        .is_some_and(|value| !valid_public_asset_url(value))
+    {
+        return error("站点 Logo 必须使用 HTTPS 地址", 400);
+    }
     if input
         .default_theme
         .as_deref()
@@ -639,10 +639,13 @@ async fn settings_patch(req: &mut Request, ctx: &RouteContext) -> Result<Respons
     }
     if input
         .background_url
-        .as_ref()
-        .is_some_and(|value| value.chars().count() > 1000)
+        .as_deref()
+        .is_some_and(|value| !valid_background_urls(value))
     {
-        return error("背景地址过长", 400);
+        return error(
+            "背景地址无效：请使用 HTTPS 地址，浅色和深色可用 | 分隔",
+            400,
+        );
     }
     if input.theme_options.as_ref().is_some_and(|value| {
         let Some(options) = value.as_object() else {
@@ -751,12 +754,11 @@ async fn settings_patch(req: &mut Request, ctx: &RouteContext) -> Result<Respons
     {
         return error("界面语言仅支持简体中文或 English", 400);
     }
-    if input.favicon_url.as_deref().is_some_and(|value| {
-        !value.trim().is_empty()
-            && Url::parse(value.trim())
-                .ok()
-                .is_none_or(|url| url.scheme() != "https")
-    }) {
+    if input
+        .favicon_url
+        .as_deref()
+        .is_some_and(|value| !valid_public_asset_url(value))
+    {
         return error("站点图标必须使用 HTTPS 地址", 400);
     }
     let password_hash = if input
diff --git a/src/routes/public.rs b/src/routes/public.rs
index a1404c5..8de5986 100644
--- a/src/routes/public.rs
+++ b/src/routes/public.rs
@@ -15,6 +15,13 @@ use crate::{
     set_admin_session_cookie, store_history_response, API_JSON_MAX_BYTES,
 };
 
+fn request_hostname(req: &Request) -> Option<String> {
+    req.url()
+        .ok()?
+        .host_str()
+        .map(|hostname| hostname.to_string())
+}
+
 pub(crate) async fn route(mut req: Request, ctx: &RouteContext) -> Result<RouteOutcome> {
     let method = req.method();
     let path = req.path();
@@ -76,6 +83,7 @@ fn config_value(ctx: &RouteContext) -> serde_json::Value {
         "site_name": settings.site_name,
         "site_description": settings.site_description,
         "site_announcement": settings.site_announcement,
+        "logo_url": settings.logo_url,
         "favicon_url": settings.favicon_url,
         "locale": settings.locale,
         "public_dashboard": settings.public_dashboard,
@@ -181,10 +189,15 @@ async fn admin_login(req: &mut Request, ctx: &RouteContext) -> Result<Response>
     }
     let login_turnstile_enabled = ctx.public_turnstile_enabled || ctx.login_protection_enabled;
     if login_turnstile_enabled {
+        let Some(hostname) = request_hostname(req) else {
+            return error("请求主机名无效", 400);
+        };
         let verified = turnstile::verify(
             &input.turnstile_token,
             &ctx.turnstile_secret_key,
             client_ip(req).as_deref(),
+            &hostname,
+            turnstile::ADMIN_LOGIN_ACTION,
         )
         .await
         .unwrap_or(false);
@@ -229,10 +242,15 @@ async fn turnstile_verify(req: &mut Request, ctx: &RouteContext) -> Result<Respo
             Ok(value) => value,
             Err(_) => return error("验证请求格式无效", 400),
         };
+    let Some(hostname) = request_hostname(req) else {
+        return error("请求主机名无效", 400);
+    };
     let verified = turnstile::verify(
         &input.token,
         &ctx.turnstile_secret_key,
         client_ip(req).as_deref(),
+        &hostname,
+        turnstile::PUBLIC_DASHBOARD_ACTION,
     )
     .await
     .unwrap_or(false);
diff --git a/src/theme.rs b/src/theme.rs
index 8b8b5cc..6bbba78 100644
--- a/src/theme.rs
+++ b/src/theme.rs
@@ -368,18 +368,7 @@ pub async fn remote_theme_version(base: &str) -> Option<String> {
 
 #[cfg(test)]
 mod tests {
-    use super::{
-        asset_url, builtin_settings_schema, normalize_url, resolve_url, validate_settings_schema,
-    };
-
-    #[test]
-    fn exposes_builtin_glass_theme_settings() {
-        let schema = builtin_settings_schema();
-        let settings = schema["settings"].as_array().expect("settings");
-        assert!(settings.iter().any(|field| field["key"] == "assetCurrency"));
-        assert!(settings.iter().any(|field| field["key"] == "enableBlur"));
-        assert_eq!(schema["source"], "builtin");
-    }
+    use super::{asset_url, normalize_url, resolve_url, validate_settings_schema};
 
     #[test]
     fn validates_remote_theme_settings() {
diff --git a/src/turnstile.rs b/src/turnstile.rs
index a65369a..a6f9109 100644
--- a/src/turnstile.rs
+++ b/src/turnstile.rs
@@ -1,7 +1,14 @@
+use std::time::Duration;
+
 use serde::{Deserialize, Serialize};
-use worker::{wasm_bindgen::JsValue, Fetch, Method, Request, RequestInit, Result};
+use worker::{wasm_bindgen::JsValue, Method, Request, RequestInit, Result};
+
+use crate::outbound::fetch_with_timeout;
 
 const SITEVERIFY_URL: &str = "https://challenges.cloudflare.com/turnstile/v0/siteverify";
+const VERIFY_TIMEOUT_SECONDS: u64 = 8;
+pub const ADMIN_LOGIN_ACTION: &str = "admin-login";
+pub const PUBLIC_DASHBOARD_ACTION: &str = "public-dashboard";
 
 #[derive(Serialize)]
 struct VerifyRequest<'a> {
@@ -11,13 +18,39 @@ struct VerifyRequest<'a> {
     remoteip: Option<&'a str>,
 }
 
-#[derive(Deserialize)]
+#[derive(Debug, Deserialize)]
 struct VerifyResponse {
     success: bool,
+    hostname: Option<String>,
+    action: Option<String>,
 }
 
-pub async fn verify(token: &str, secret: &str, remote_ip: Option<&str>) -> Result<bool> {
-    if token.is_empty() || token.len() > 2048 || secret.is_empty() {
+fn matches_request(
+    response: &VerifyResponse,
+    expected_hostname: &str,
+    expected_action: &str,
+) -> bool {
+    response.success
+        && response
+            .hostname
+            .as_deref()
+            .is_some_and(|hostname| hostname.eq_ignore_ascii_case(expected_hostname))
+        && response.action.as_deref() == Some(expected_action)
+}
+
+pub async fn verify(
+    token: &str,
+    secret: &str,
+    remote_ip: Option<&str>,
+    expected_hostname: &str,
+    expected_action: &str,
+) -> Result<bool> {
+    if token.is_empty()
+        || token.len() > 2048
+        || secret.is_empty()
+        || expected_hostname.is_empty()
+        || expected_action.is_empty()
+    {
         return Ok(false);
     }
 
@@ -32,10 +65,59 @@ pub async fn verify(token: &str, secret: &str, remote_ip: Option<&str>) -> Resul
     let request = Request::new_with_init(SITEVERIFY_URL, &init)?;
     request.headers().set("Content-Type", "application/json")?;
 
-    let mut response = Fetch::Request(request).send().await?;
+    let Some(mut response) =
+        fetch_with_timeout(request, Duration::from_secs(VERIFY_TIMEOUT_SECONDS)).await?
+    else {
+        return Ok(false);
+    };
     if !(200..300).contains(&response.status_code()) {
         return Ok(false);
     }
     let result: VerifyResponse = response.json().await?;
-    Ok(result.success)
+    Ok(matches_request(&result, expected_hostname, expected_action))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{matches_request, VerifyResponse};
+
+    fn response(hostname: &str, action: &str) -> VerifyResponse {
+        VerifyResponse {
+            success: true,
+            hostname: Some(hostname.to_string()),
+            action: Some(action.to_string()),
+        }
+    }
+
+    #[test]
+    fn accepts_matching_hostname_and_action() {
+        assert!(matches_request(
+            &response("status.example.com", "admin-login"),
+            "STATUS.EXAMPLE.COM",
+            "admin-login",
+        ));
+    }
+
+    #[test]
+    fn rejects_mismatched_or_incomplete_context() {
+        assert!(!matches_request(
+            &response("other.example.com", "admin-login"),
+            "status.example.com",
+            "admin-login",
+        ));
+        assert!(!matches_request(
+            &response("status.example.com", "public-dashboard"),
+            "status.example.com",
+            "admin-login",
+        ));
+        assert!(!matches_request(
+            &VerifyResponse {
+                success: true,
+                hostname: None,
+                action: None,
+            },
+            "status.example.com",
+            "admin-login",
+        ));
+    }
 }