diff --git a/backend/routers/router.go b/backend/routers/router.go
index 5c3b5fb..2585696 100644
--- a/backend/routers/router.go
+++ b/backend/routers/router.go
@@ -92,6 +92,11 @@ func SetupRouter() *gin.Engine {
 		logs.GET("/labels", logsCtrl.Labels)
 		logs.GET("/label/:name/values", logsCtrl.LabelValues)
 		logs.GET("/my-scope", logsCtrl.MyScope)
+		// ⚠️ 必须是 POST：前端 logsApi.histogram 用 POST 传 body（sourceId/query/start/end）。
+		// 曾被误改成 GET，导致 POST /logs/histogram 全部 404，
+		// 表现为日志查询页直方图不显示、分析页直接报 "API endpoint not found"。
+		// 同时保留 GET 作为简单调试入口（参数放 query string）。
+		logs.POST("/histogram", logsCtrl.Histogram)
 		logs.GET("/histogram", logsCtrl.Histogram)
 		logs.GET("/daily-volume", logsCtrl.DailyVolume)
 		// 总量统计（index/stats）：只读索引，用于算总页数
diff --git a/backend/routers/router_test.go b/backend/routers/router_test.go
new file mode 100644
index 0000000..1ef4864
--- /dev/null
+++ b/backend/routers/router_test.go
@@ -0,0 +1,80 @@
+package routers
+
+import (
+	"testing"
+
+	"github.com/gin-gonic/gin"
+)
+
+// 回归：接口的 **HTTP 方法与路径** 必须和前端调用一致。
+//
+// 线上事故：一次模糊匹配的 patch 把
+//     logs.POST("/histogram", ...)  →  logs.GET("/histogram", ...)
+// 前端 logsApi.histogram 用的是 POST（body 里带 sourceId/query/start/end），
+// 于是所有直方图请求 404：
+//   - 日志查询页：直方图不显示
+//   - 日志分析页：直接报 "API endpoint not found"，整页不可用
+// 这类"方法写错"编译期完全查不出来，只能靠路由表断言。
+func TestCriticalRoutes(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	engine := SetupRouter()
+
+	// 期望的 method + path（注意 gin 会把 :param 保留为 :id）
+	expect := []struct{ method, path string }{
+		// 日志查询 / 分析页的数据来源：必须是 POST（前端传 body）
+		{"POST", "/api/v1/logs/histogram"},
+		{"POST", "/api/v1/logs/stats"},
+		{"POST", "/api/v1/logs/metrics"},
+		{"POST", "/api/v1/logs/query"},
+		{"POST", "/api/v1/logs/context"},
+		// 查询辅助接口：GET + query string
+		{"GET", "/api/v1/logs/sources"},
+		{"GET", "/api/v1/logs/labels"},
+		{"GET", "/api/v1/logs/label/:name/values"},
+		{"GET", "/api/v1/logs/my-scope"},
+		{"GET", "/api/v1/logs/daily-volume"},
+		{"GET", "/api/v1/logs/health"},
+		// 告警
+		{"GET", "/api/v1/alerts/rules"},
+		{"POST", "/api/v1/alerts/rules"},
+		{"GET", "/api/v1/alerts/channels"},
+		{"POST", "/api/v1/alerts/check"},
+		{"GET", "/api/v1/alerts/deliveries"},
+		// 审计 / 自检 / 备份
+		{"GET", "/api/v1/audit-logs"},
+		{"GET", "/api/v1/system/self-check"},
+		{"GET", "/api/v1/system/backup"},
+	}
+
+	registered := map[string]bool{}
+	for _, route := range engine.Routes() {
+		registered[route.Method+" "+route.Path] = true
+	}
+
+	for _, item := range expect {
+		key := item.method + " " + item.path
+		if !registered[key] {
+			t.Errorf("缺少路由: %s（前端按这个方法和路径调用，缺了就是 404）", key)
+		}
+	}
+}
+
+// 回归：前端用 POST 的接口不能只有 GET 版本。
+// 单独断言一次，避免以后又有人"顺手"把 POST 改成 GET。
+func TestHistogramAcceptsPost(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	engine := SetupRouter()
+
+	methods := map[string]bool{}
+	for _, route := range engine.Routes() {
+		if route.Path == "/api/v1/logs/histogram" {
+			methods[route.Method] = true
+		}
+	}
+	if !methods["POST"] {
+		t.Fatal("POST /api/v1/logs/histogram 未注册：前端 logsApi.histogram 用 POST，会 404")
+	}
+	if !methods["GET"] {
+		t.Fatal("GET /api/v1/logs/histogram 未注册：curl 调试入口丢了")
+	}
+}
diff --git a/frontend/src/components/Layout.tsx b/frontend/src/components/Layout.tsx
index 91164be..ed89bab 100644
--- a/frontend/src/components/Layout.tsx
+++ b/frontend/src/components/Layout.tsx
@@ -16,7 +16,6 @@ import {
   Menu,
   Sun,
   Moon,
-  Settings,
 } from 'lucide-react'
 import { useTheme } from 'next-themes'
 import { useTranslation } from 'react-i18next'
@@ -238,17 +237,6 @@ const Layout = memo(function Layout({ children }: { children: React.ReactNode })
             </h1>
           </div>
           <div className="flex items-center gap-4 flex-shrink-0">
-            {/* 系统设置入口：低频平台配置，放右上角比占侧栏一位更合适 */}
-            {user?.role === 'admin' && (
-              <Link
-                to="/settings"
-                title={t('menu.settings')}
-                aria-label={t('menu.settings')}
-                className="flex items-center gap-1 rounded-lg px-2.5 py-1.5 text-muted-foreground transition-all hover:bg-muted hover:text-foreground"
-              >
-                <Settings className="w-4 h-4" />
-              </Link>
-            )}
             <ThemeToggle />
             {user && (
               <div className="flex items-center gap-3 text-sm text-muted-foreground">
diff --git a/frontend/src/i18n/locales/en/common.ts b/frontend/src/i18n/locales/en/common.ts
index 3b93a2d..5a1ce1c 100644
--- a/frontend/src/i18n/locales/en/common.ts
+++ b/frontend/src/i18n/locales/en/common.ts
@@ -5,7 +5,7 @@ export default {
     groups: {
       resources: 'Resources',
       services: 'Log Service',
-      system: 'Users & Audit',
+      system: 'System Settings',
     },
     dashboard: 'Dashboard',
     wizard: 'Deploy Wizard',
@@ -17,7 +17,9 @@ export default {
     logs: 'Log Query',
     alerts: 'Alerts',
     analysis: 'Log Analysis',
-    settings: 'Settings',
+    settings: 'General',
+    ldap: 'LDAP',
+    registry: 'Image Registry',
     users: 'Users',
     audit: 'Audit Log',
     login: 'Sign In',
diff --git a/frontend/src/i18n/locales/en/settings.ts b/frontend/src/i18n/locales/en/settings.ts
index 9eecc40..6eb0553 100644
--- a/frontend/src/i18n/locales/en/settings.ts
+++ b/frontend/src/i18n/locales/en/settings.ts
@@ -1,11 +1,9 @@
 // settings namespace — Settings page (general/password/about, notifications, LDAP, image registry), English copy.
 // Note: theme & language card titles and ThemeSection copy are owned elsewhere and are not in this dictionary.
 export default {
-  title: 'Settings',
-  description: 'General settings, alert notifications, LDAP integration, and the default image registry',
+  title: 'General',
   tabs: {
     general: 'General',
-    notify: 'Alert Notifications',
     ldap: 'LDAP Integration',
     registry: 'Default Image Registry',
   },
diff --git a/frontend/src/i18n/locales/zh/common.ts b/frontend/src/i18n/locales/zh/common.ts
index 31a5d83..e0981b0 100644
--- a/frontend/src/i18n/locales/zh/common.ts
+++ b/frontend/src/i18n/locales/zh/common.ts
@@ -5,7 +5,7 @@ export default {
     groups: {
       resources: '资源接入',
       services: '日志服务',
-      system: '用户与审计',
+      system: '系统设置',
     },
     dashboard: '仪表盘',
     wizard: '部署向导',
@@ -17,7 +17,9 @@ export default {
     logs: '日志查询',
     alerts: '日志告警',
     analysis: '日志分析',
-    settings: '系统设置',
+    settings: '通用配置',
+    ldap: 'LDAP 接入',
+    registry: '默认镜像源',
     users: '用户管理',
     audit: '审计日志',
     login: '登录',
diff --git a/frontend/src/i18n/locales/zh/settings.ts b/frontend/src/i18n/locales/zh/settings.ts
index 418c732..ce36e52 100644
--- a/frontend/src/i18n/locales/zh/settings.ts
+++ b/frontend/src/i18n/locales/zh/settings.ts
@@ -1,11 +1,9 @@
 // settings 命名空间 — 系统设置页(通用配置/密码/关于、告警通知、LDAP 接入、镜像源)中文文案
 // 注意:主题卡片与语言卡片的标题、ThemeSection 内文案由其他模块负责,不在本词典内。
 export default {
-  title: '系统设置',
-  description: '通用配置、告警通知、LDAP 接入与默认镜像源',
+  title: '通用配置',
   tabs: {
     general: '通用配置',
-    notify: '告警通知',
     ldap: 'LDAP 接入',
     registry: '默认镜像源',
   },
diff --git a/frontend/src/pages/settings/index.tsx b/frontend/src/pages/settings/index.tsx
index ab21688..1dea3c1 100644
--- a/frontend/src/pages/settings/index.tsx
+++ b/frontend/src/pages/settings/index.tsx
@@ -10,12 +10,9 @@ import { authApi } from '@/api'
 import { clearAuth } from '@/lib/auth-storage'
 import { toast } from 'sonner'
 import { PageContainer } from '@/components/PageContainer'
-import { LdapSection } from './components/LdapSection'
 import { ThemeSection } from './components/ThemeSection'
 import { LanguageSection } from '@/i18n/LanguageSection'
 import { Palette } from 'lucide-react'
-import { ImageRegistrySection } from './components/ImageRegistrySection'
-import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs'
 
 // 构建指纹由 vite define 注入；本地 tsc/预览时回退
 const APP_VERSION = typeof __APP_VERSION__ !== 'undefined' ? __APP_VERSION__ : 'dev'
@@ -70,16 +67,10 @@ const SettingsPage = memo(function SettingsPage() {
   )
 
   return (
-    <PageContainer title={t('title')} description={t('description')}>
-      <Tabs defaultValue="general" className="space-y-6">
-        <TabsList>
-          <TabsTrigger value="general">{t('tabs.general')}</TabsTrigger>
-          <TabsTrigger value="notify">{t('tabs.notify')}</TabsTrigger>
-          <TabsTrigger value="ldap">{t('tabs.ldap')}</TabsTrigger>
-          <TabsTrigger value="registry">{t('tabs.registry')}</TabsTrigger>
-        </TabsList>
-
-        <TabsContent value="general" className="space-y-6">
+    <PageContainer title={t('title')}>
+      {/* 不再有内层 tab：LDAP / 镜像源 已拆成独立路由，
+          由左侧「系统设置」分组的顶层 tab 切换（单层 tab 更好理解）。 */}
+      <div className="space-y-6">
         {/* 外观与语言(紧凑单卡:主题分段器 + 语言分段器) */}
         <Card className="border-border">
           <CardHeader className="pb-3">
@@ -176,20 +167,7 @@ const SettingsPage = memo(function SettingsPage() {
         </Card>
 
       </div>
-        </TabsContent>
-
-        <TabsContent value="notify" className="space-y-6">
-          {/* 告警通知通道已移到「日志告警 → 通知通道」，避免配置入口分裂 */}
-        </TabsContent>
-
-        <TabsContent value="ldap">
-          <LdapSection />
-        </TabsContent>
-
-        <TabsContent value="registry" className="space-y-6">
-          <ImageRegistrySection />
-        </TabsContent>
-      </Tabs>
+      </div>
     </PageContainer>
   )
 })
diff --git a/frontend/src/pages/settings/ldap.tsx b/frontend/src/pages/settings/ldap.tsx
new file mode 100644
index 0000000..8461b5f
--- /dev/null
+++ b/frontend/src/pages/settings/ldap.tsx
@@ -0,0 +1,16 @@
+import { memo } from 'react'
+import { useTranslation } from 'react-i18next'
+import { PageContainer } from '@/components/PageContainer'
+import { LdapSection } from './components/LdapSection'
+
+/** LDAP 接入：从系统设置里拆出来，作为侧栏「系统设置」分组的一个 tab */
+export const LdapPage = memo(function LdapPage() {
+  const { t } = useTranslation('settings')
+  return (
+    <PageContainer title={t('tabs.ldap')}>
+      <LdapSection />
+    </PageContainer>
+  )
+})
+
+export default LdapPage
diff --git a/frontend/src/pages/settings/registry.tsx b/frontend/src/pages/settings/registry.tsx
new file mode 100644
index 0000000..69e945c
--- /dev/null
+++ b/frontend/src/pages/settings/registry.tsx
@@ -0,0 +1,16 @@
+import { memo } from 'react'
+import { useTranslation } from 'react-i18next'
+import { PageContainer } from '@/components/PageContainer'
+import { ImageRegistrySection } from './components/ImageRegistrySection'
+
+/** 默认镜像源：从系统设置里拆出来，作为侧栏「系统设置」分组的一个 tab */
+export const RegistryPage = memo(function RegistryPage() {
+  const { t } = useTranslation('settings')
+  return (
+    <PageContainer title={t('tabs.registry')}>
+      <ImageRegistrySection />
+    </PageContainer>
+  )
+})
+
+export default RegistryPage
diff --git a/frontend/src/router/routes.tsx b/frontend/src/router/routes.tsx
index 7315f06..8233d87 100644
--- a/frontend/src/router/routes.tsx
+++ b/frontend/src/router/routes.tsx
@@ -17,6 +17,8 @@ import {
   BarChart3,
   History,
   Boxes,
+  ShieldCheck,
+  Container,
 } from 'lucide-react';
 import type { AppRoute, MenuItem, RouteMeta } from '@/types/router';
 
@@ -28,6 +30,8 @@ const Storage = lazy(() => import('@/pages/storage'));
 const Deployments = lazy(() => import('@/pages/deployments'));
 const Collectors = lazy(() => import('@/pages/collectors'));
 const SettingsPage = lazy(() => import('@/pages/settings'));
+const LdapPage = lazy(() => import('@/pages/settings/ldap'));
+const RegistryPage = lazy(() => import('@/pages/settings/registry'));
 const NotFound = lazy(() => import('@/pages/not-found'));
 const WizardPage = lazy(() => import('@/pages/wizard'));
 const LogsPage = lazy(() => import('@/pages/logs'));
@@ -76,14 +80,23 @@ export const routes: AppRoute[] = [
   {
     path: '/users', component: UsersPage, auth: true,
     meta: {
-      title: 'menu.users', icon: UsersRound, order: 8, adminOnly: true,
+      // 系统设置（tab 起点）/ 用户管理 / 审计日志 同属「系统设置」分组，
+      // 侧栏只占一个入口，页面内用 tab 切换。
+      title: 'menu.users', icon: UsersRound, order: 9, adminOnly: true,
+      groupKey: 'system',
+    },
+  },
+  { path: '/audit', component: AuditPage, auth: true, meta: { title: 'menu.audit', icon: History, order: 10, adminOnly: true, groupKey: 'system' } },
+  { path: '/settings/ldap', component: LdapPage, auth: true, meta: { title: 'menu.ldap', icon: ShieldCheck, order: 11, adminOnly: true, groupKey: 'system' } },
+  { path: '/settings/registry', component: RegistryPage, auth: true, meta: { title: 'menu.registry', icon: Container, order: 12, adminOnly: true, groupKey: 'system' } },
+  // 系统设置放回侧栏，并作为「系统设置」分组的 tab 起点（order 最小 = 排在第一个）
+  {
+    path: '/settings', component: SettingsPage, auth: true,
+    meta: {
+      title: 'menu.settings', icon: Settings, order: 8, adminOnly: true,
       group: { key: 'system', label: 'menu.groups.system', icon: Settings, order: 8 },
     },
   },
-  { path: '/audit', component: AuditPage, auth: true, meta: { title: 'menu.audit', icon: History, order: 13, adminOnly: true, groupKey: 'system' } },
-  // 系统设置从侧栏移到右上角齿轮入口：属于低频平台配置，
-  // 和「用户/审计」这类日常安全管理不是一类东西，混在一个分组里太乱。
-  { path: '/settings', component: SettingsPage, auth: true, meta: { title: 'menu.settings', icon: Settings, order: 12, adminOnly: true, hideInMenu: true } },
   { path: '*', component: NotFound, auth: false, meta: { title: 'menu.notFound', hideInMenu: true } },
 ];